AD and MRPB

[Zovs]

Steve posted some useful stuff on the old TOAW III forums upon this subject.

According to Steve, Bob Cross (aka Curtis Lemay - a famous WWII US Officer, note that Bob Cross is not really Curtis, he just is using him as a meme, ditto for Lobster, wherein he is not Nigel the Author but Jack) stated this as a starting point table?

Whole-week: 2
Half-week: 4
Full-day: 14
Half-day: 28
6-hour: 56

So we have some gaps here.

Mainly:

Code: Select all

 Annual:     ??
 Seasonal:   ??
 Monthly:    ??
 Two week:   ??
 Full week:   2
 Half week:   4
 Full day:   14
 Half day:   28
 Six hour:   56
 Three hour: ??
 One hour:   ??
 

So what would be good estimates for the missing values?
I don't see the logic here, 2 doubled goes to 4, but then the jump from 4 to 14, no logical sense, then 14 doubles to 28, then 28 doubles to 56, do we continue doubling 56 to 112 and then double that to 224? What about the Monthly values? Is that 1? Seasonal and Annually?

Thoughts?

[76mm]

ORIGINAL: Zovs
I don't see the logic here, 2 doubled goes to 4, but then the jump from 4 to 14, no logical sense, then 14 doubles to 28, then 28 doubles to 56,

The logic seems pretty clear: it if a function of the length of the period. a full week is two, a half week, half as long, is twice as much. A half week--3.5 days--is 3.5 x 1 day = 3.5 x 4 = 14. Whether that logic provides the best results, I have no idea.

In my scenario with six hour turns, I'm using an MRPB of 9, although I've also reduced the attrition factor (or whatever its called) to 4 from the default of 10. This results in a rather high lethality rate, which is what I wanted.

[golden delicious]

I think this direct scaling of the Attrition Divider with turn length is a mistake.

Consider a typical scenario. You have half-week turns. Things aren't working out in your testing and you switch to full-week turns.

All your units now have double their movement allowances on any given turn. Does the amount of combat in a single turn stay the same as it was with half week turns- or does it increase significantly?

So if you halve the attrition divider while doubling the turn length, have you kept losses the same- or increased them significantly?

There's a load of other factors around turn length. I actually wrote an article on it a while back but only about four people saw it. Hold on.

[Zovs]

Hence my questions. I have been digging through a boat load of scenarios to come up with a good formula. In that process I have begun a database of sorts. I can share this later if there is interest once it's more flushed out.

So any help in understand the matrix is valuable.

And I do mean matrix, otherwise the values in the singular are meaningless.

For example in my testing and digging through scenarios to gain an understanding of all these concepts and in the creation of my database I have uncovered the following basic factors that are needed to understand how they all relate:

Km or Meters Per Hex (0.25, 0.50, 1, 2.5, 5, 10, 15, 20, 25, 50, 100, 200)
Turn Length (One hour, Three hour, Six hour, Half day, Full day, Half week, Full week, Two Week, Monthly, Seasonal, Annually)
Attrition Divider #
MRPB #
Unit Scale (Army, Corps, Division, Brigade, Regiment, Battalion, or combinations thereof).

[Zovs]

ORIGINAL: 76mm

ORIGINAL: Zovs
I don't see the logic here, 2 doubled goes to 4, but then the jump from 4 to 14, no logical sense, then 14 doubles to 28, then 28 doubles to 56,

The logic seems pretty clear: it if a function of the length of the period. a full week is two, a half week, half as long, is twice as much. A half week--3.5 days--is 3.5 x 1 day = 3.5 x 4 = 14. Whether that logic provides the best results, I have no idea.

In my scenario with six hour turns, I'm using an MRPB of 9, although I've also reduced the attrition factor (or whatever its called) to 4 from the default of 10. This results in a rather high lethality rate, which is what I wanted.

Not sure if it is quite that clear.

D21 is AD 6 and MRPB 3 while FitE2 1.9 is AD 6 and MRPB 4, both are 10 km per hex and Half week turns. Weserubung is 5km per hex and Half Day turns with AD 15 and MRPB of 3. Russia-Japan 1905 at 10km per hex and Full week turns uses AD 30 and MRBP of 7.

So not so cut and dry...

[golden delicious]

ORIGINAL: Zovs

Not sure if it is quite that clear.

D21 is AD 6 and MRPB 3 while FitE2 1.9 is AD 6 and MRPB 4, both are 10 km per hex and Half week turns. Weserubung is 5km per hex and Half Day turns with AD 15 and MRPB of 3. Russia-Japan 1905 at 10km per hex and Full week turns uses AD 30 and MRBP of 7.

So not so cut and dry...

There is very much not a "right" answer for combinations of these factors. Some extreme setting combinations are obviously going to produce extreme results, but one should test and design in multiple cycles rather than trying to second-guess the correct settings for everything from the outset.

I'd start with the map and unit scale combination, as one needs to design the map and OOB in a lot of detail whereas the other factors are just variables that can be changed at a whim. Typically the map scale comes first based on the type of scenario you're trying to make and the size of the theatre. From there, you should ask, what's the smallest unit which could realistically be expect to prevent enemy units passing through a hex at this scale? That should be your smallest combat unit- so if you're going to allow players to divide units, you'll need the "normal" unit size to be one step up from that. For example, you might decide that a battalion could effectively screen a 10km hex, but a company couldn't. In that case, you'd want most combat units to be regiments, and any auxiliary units of a smaller size should be given the section icon to prevent them from dividing.

From there you can play around with various settings until it feels right. I just posted an article about various factors around turn length but I'm afraid I don't really give any straight answers there either

[76mm]

ORIGINAL: Zovs
Not sure if it is quite that clear.
***
So not so cut and dry...

Sorry, what I was trying to say that it is pretty clear how they came up the the numbers...but whether those numbers are "correct" or appropriate, especially as other parameters change, is a different matter.

[Lobster]

I try and match verified real world casualties. Not encirclements, POW or MIA but casualties. Encirclements tend to cause units to disintegrate so I avoid them for this purpose. Obviously players will not take a historical path. For example if you were doing a scenario of Poland in 1939 Case White the Invasion of Poland by Robert Forczyk has some excellent example of casualties in battles for both sides.

[Curtis Lemay]

ORIGINAL: golden delicious

I think this direct scaling of the Attrition Divider with turn length is a mistake.

Consider a typical scenario. You have half-week turns. Things aren't working out in your testing and you switch to full-week turns.

All your units now have double their movement allowances on any given turn. Does the amount of combat in a single turn stay the same as it was with half week turns- or does it increase significantly?

So if you halve the attrition divider while doubling the turn length, have you kept losses the same- or increased them significantly?

There's a load of other factors around turn length. I actually wrote an article on it a while back but only about four people saw it. Hold on.

There are still just 10 rounds per turn. So, unless the MPs per unit are so low that no unit can reach the full 10 rounds, then, yes, the amount of combat should stay about the same (10 rounds). When you consider that changes in turn interval usually involve a change in map scale as well, MPs tend to remain about the same.

So, if you have 5km and full day turns compared to 2.5km and half-day turns, you've got the same MPs, so the same chance of getting all 10 rounds in. Clearly, the former needs to be twice as bloody as the latter, all else being equal.

If your scale only allows less than 5 MPs per unit, you probably need a different scale regardless.

[golden delicious]

ORIGINAL: Curtis Lemay

There are still just 10 rounds per turn. So, unless the MPs per unit are so low that no unit can reach the full 10 rounds, then, yes, the amount of combat should stay about the same (10 rounds).

There are ten rounds for sure. The chance of a unit fighting for all ten rounds is pretty low, however.

Let's say I'm attacking. I get forward a hex in the first round, but not everyone advances and a lot of my artillery is out of range. I have to move everyone forward. It may take 2 MPs to move forward one hex. If my units have 10 MPs, that's two rounds gone. If they have 20 MPs, that's one round gone.

When you consider that changes in turn interval usually involve a change in map scale as well, MPs tend to remain about the same.

And unit scale. In a typical attack by 1st Division, what % of the riflemen will be engaged? What's the % if 1st Regiment goes into the attack? In practice, the bigger the unit, the more of it will be held back or simply not be able to get fully into action.

Then, too, I've played scenarios with Attrition Divider settings at the extremes. They feel wrong. I would advise against pushing this factor outside the range of about 7-15.

[Zovs]

ORIGINAL: golden delicious

ORIGINAL: Zovs

Not sure if it is quite that clear.

D21 is AD 6 and MRPB 3 while FitE2 1.9 is AD 6 and MRPB 4, both are 10 km per hex and Half week turns. Weserubung is 5km per hex and Half Day turns with AD 15 and MRPB of 3. Russia-Japan 1905 at 10km per hex and Full week turns uses AD 30 and MRBP of 7.

So not so cut and dry...

There is very much not a "right" answer for combinations of these factors. Some extreme setting combinations are obviously going to produce extreme results, but one should test and design in multiple cycles rather than trying to second-guess the correct settings for everything from the outset.

I'd start with the map and unit scale combination, as one needs to design the map and OOB in a lot of detail whereas the other factors are just variables that can be changed at a whim. Typically the map scale comes first based on the type of scenario you're trying to make and the size of the theatre. From there, you should ask, what's the smallest unit which could realistically be expect to prevent enemy units passing through a hex at this scale? That should be your smallest combat unit- so if you're going to allow players to divide units, you'll need the "normal" unit size to be one step up from that. For example, you might decide that a battalion could effectively screen a 10km hex, but a company couldn't. In that case, you'd want most combat units to be regiments, and any auxiliary units of a smaller size should be given the section icon to prevent them from dividing.

From there you can play around with various settings until it feels right. I just posted an article about various factors around turn length but I'm afraid I don't really give any straight answers there either

Thanks Ben this is good advice.

Mainly I am just trying to get a good baseline which I think is possible, based on the database I am building up.

[Zovs]

Thanks Tom, Jack and Ben and also Bob (although your post could use a little more explaining).

These are useful posts for uncovering the 'secrets' of the beast that lies within.

Personally I think these should be provided to help designer make the best possible choice and then adjust from there.

The database I am creating is pretty revealing and I do get the need for making things feel right. But there should be a base line and that base line should be explainable.

[Curtis Lemay]

ORIGINAL: golden delicious

Let's say I'm attacking. I get forward a hex in the first round, but not everyone advances and a lot of my artillery is out of range. I have to move everyone forward. It may take 2 MPs to move forward one hex. If my units have 10 MPs, that's two rounds gone. If they have 20 MPs, that's one round gone.

Advances into territory that started the turn enemy controlled is a percentage cost. So, the cost may be higher for the doubled MP units. Regardless, some units attacking a fortified line will tend to expend most of that 10 rounds. They will break through twice as fast unless there is an AD change.

And unit scale. In a typical attack by 1st Division, what % of the riflemen will be engaged? What's the % if 1st Regiment goes into the attack? In practice, the bigger the unit, the more of it will be held back or simply not be able to get fully into action.

What difference does it make what size units are used? It's still just X amount of force attacking Y amount of force.

Then, too, I've played scenarios with Attrition Divider settings at the extremes. They feel wrong. I would advise against pushing this factor outside the range of about 7-15.

Results trump "feelings".

[Zovs]

So here is a snippet of the database file I am creating. I can see some trends, once it is built up, then I'll add some meaningful sorting and filtering into it.

[golden delicious]

ORIGINAL: Curtis Lemay

Advances into territory that started the turn enemy controlled is a percentage cost.

The hex conversion is a % but the terrain cost is an absolute. Because it's usually quite a small % and there's a rounding factor, a unit with 19 move will pay 2 MPs and a unit with 6 move will also pay 2 MPs.

Regardless, some units attacking a fortified line will tend to expend most of that 10 rounds. They will break through twice as fast unless there is an AD change.

No because they will also take double the casualties, and so be much more likely to break off early. There's another point for you: in a given combat, you're likely to have fewer units fighting on second and subsequent rounds if the AD is higher.

Moreover, you're treating units fighting in a static engagement as the norm when it is really more of an exception. Fortified lines tend to in reality be multiple lines- and again, here's where your model breaks down. At some scales, those lines may be in distinct hexes- and you'll have to move to get in touch with the others. At other scales, the lines will be in the same hex, and in these cases, you should not assume that the whole defending unit is fighting in any given combat: the second line units will be waiting in their positions.

What difference does it make what size units are used? It's still just X amount of force attacking Y amount of force.

No, you're wrong. A unit in TOAW either attacks or it doesn't, but if you were to zoom in to a lower scale, some of the elements of the unit would actually not attack. As such your design needs to ensure that what happens when one division attacks another is as close as possible to how it would look if you were to zoom in: you have to assume that only a certain portion of the unit will actually fight.

Results trump "feelings".

All you've done is present flawed logic, not "results". Your approach is typically extremely purist, and you systematically exclude factors which mitigate or conflict with what you see as the single driving force which decides everything. It's absolutely important for the designer to consider Attrition Divider, and all else being equal a longer turn scale will tend to favour a lower attrition divider, but the idea of this being an inverse proportion as if we were talking about the force of gravity or something is too absolutist for scenario design, which is far more art than science.

[golden delicious]

ORIGINAL: Zovs

So here is a snippet of the database file I am creating. I can see some trends, once it is built up, then I'll add some meaningful sorting and filtering into it.

I'd suggest breaking out the year into another column as you're likely to find that increased firepower will produce lower unit scales as time goes on.

[golden delicious]

[deleted]

[Zovs]

+1 and good point on the year...

[cathar1244]

One thought about movement rates -- rates of advance typically flatten out over time (weeks, months). Well documented in Dupuy's works.

Cheers

[Curtis Lemay]

ORIGINAL: golden delicious

The hex conversion is a % but the terrain cost is an absolute. Because it's usually quite a small % and there's a rounding factor, a unit with 19 move will pay 2 MPs and a unit with 6 move will also pay 2 MPs.

The advancing units tend to be the most mobile - with the highest MPs. For sure this was a factor with CFNA.

No because they will also take double the casualties, and so be much more likely to break off early. There's another point for you: in a given combat, you're likely to have fewer units fighting on second and subsequent rounds if the AD is higher.

They won't take double the casualties if the AD is the same. They only take double casualties if the AD is halved. And then the defenders are taking double casualties as well - and fall back twice as fast. Fewer units fighting on second and subsequent rounds sounds like a good simulation of multiple lines of resistance you mention below:

Moreover, you're treating units fighting in a static engagement as the norm when it is really more of an exception. Fortified lines tend to in reality be multiple lines- and again, here's where your model breaks down. At some scales, those lines may be in distinct hexes- and you'll have to move to get in touch with the others. At other scales, the lines will be in the same hex, and in these cases, you should not assume that the whole defending unit is fighting in any given combat: the second line units will be waiting in their positions.

You're assuming a hex-scale change here? Note that I did Kaiserschlacht 1918 at two different scales and got the same results with both.

No, you're wrong. A unit in TOAW either attacks or it doesn't, but if you were to zoom in to a lower scale, some of the elements of the unit would actually not attack. As such your design needs to ensure that what happens when one division attacks another is as close as possible to how it would look if you were to zoom in: you have to assume that only a certain portion of the unit will actually fight.

So, if you have battalions, you'll hold a reserve out of action? But if you have regiments, you'll throw everything at them? Reserves are good ideas at any scale.

All you've done is present flawed logic, not "results". Your approach is typically extremely purist, and you systematically exclude factors which mitigate or conflict with what you see as the single driving force which decides everything. It's absolutely important for the designer to consider Attrition Divider, and all else being equal a longer turn scale will tend to favour a lower attrition divider, but the idea of this being an inverse proportion as if we were talking about the force of gravity or something is too absolutist for scenario design, which is far more art than science.

This isn't theory. I've applied it to multiple scenarios. Scenarios that work.