There are three items that may be placed in a hex to impede movement; Mines, AT Obstacles and Wire. All may be initially deployed, and mines may be hastily deployed by Engineer units during the battle.
We all know that. What you might not be aware of, though, is that Engineers adding mines to hexes that already contain any of these three obstacles are going to yield some predictable, but perhaps, unexpected results.
Here's what happens:
The program has a counter for the number of 'obstacles in the hex (N) and a counter for the types of obstacles included (T).
(disclaimer: Please note here that I am not a developer, nor have I actually seen the software code for this game. These observations are just that, and no more. End disclaimer)
Regardless of how many mines or AT obstacles you place in a hex, if there are more than one Type, the Number of obstacles is divided evenly among the types present. (ie. N/T)
Some examples:
During Deployment -
Lay 10 Mines, then lay 10 AT obstacles in the same hex. When you inquire the hex you see: "10 mines, 10 AT".
Now delete 10 mines (or 10 AT obstacles - it makes no difference).
When you inquire the hex you'll see: "5 mines, 5 AT".
During the Battle -
Set your Engineer adjacent to a predeployed AT obstacle (10 each). Change the Engineers' orders to "Will place mines...", and aim him towards the AT populated hex.
Now normally the Engineer will place 1 or 2 mines in the adjacent hex. But NOT if there's already another Type of obstacle present.
Inquire the hex now and you'll read: "5 mines, 5 AT" (it may read 6 of each if your Engineer laid 2 mines that turn).
Number of obstacles: 11 (or 12)
Types of obstacles: 2 (mines and AT)
Number of each type = N/T = 11/2 = 5 each (FRD)
This works equally well with Wire, and using all three types in a hex.
Consider:
Deploy 10 each of Mines, AT Obstacles and Wire. Now delete 20 points from the hex. An inquiry of the hex will read: 3 Mines, 3 AT, 3 Wire" (10/3). All that for only the cost of 10 "mine points".
Deploy 10 each of AT obstacles and Wire (no mines). Place Engineers adjacent to those hexes and lay mines. The first mine placed will change the hex to "7 Mines, 7 AT, 7 wire" (21/3).
I believe the same results occur when a unit (or artillery) is removing mines and obstacles. I'm not sure if certain task specific units (Sherman Flail, for instance) would still have the capability of stripping out AT obstacles in addition to the Mines or Wire.
Since the obstacles decrease in parallel, all types will be present until the entire count is removed. In other words, that AT obstacle isn't going away for a long time. At least until the Mines and/or Wire are removed too.
Also be aware that minefields are visible to the opponent if they are mixed with either of the other two obstacles.
The quickest way to remove these nasty entanglements?
Any flamethrowing vehicle will rip right through a minefield in short order.
