Custom formations vs single units question

[Daza99]

This might be dumb question(s) and wonderings. But with custom formations we can have a mix of units, which is a great feature. So I was wondering what the difference is having those formations in battle compared to having the same units as individual units in a battle. I would imagine the custom formations would have a better coordination/cohesion? is there any other benefits?

I would also presume if you have a mix of Inf and GM, would the infantry have better defense because of the higher soft defense the GM gives? and what about say tanks and infantry together, would the inf have better cover in the open using the tanks as cover? (lets say they are not being flanked) if the game even accounts for things like that?

I wonder if motorized units with infantry (eg Truck or APC) might have longer lasting supplies because they can carry more onboard?

[Winged]

This might be dumb question(s) and wonderings. But with custom formations we can have a mix of units, which is a great feature. So I was wondering what the difference is having those formations in battle compared to having the same units as individual units in a battle. I would imagine the custom formations would have a better coordination/cohesion? is there any other benefits?

The only benefit of having a custom formation is to have your own unique mix of units as a formation, everything else stays the same. Having precise control over your formation composition is important because you really want to attack with units from one formation as much as possible, since attacking with more than one formation halves your concentric attack combat bonus.

I would also presume if you have a mix of Inf and GM, would the infantry have better defense because of the higher soft defense the GM gives? and what about say tanks and infantry together, would the inf have better cover in the open using the tanks as cover? (lets say they are not being flanked) if the game even accounts for things like that?

Allied troops do not affect each other in any way in combat, apart from shield generator models giving your troops a shield (I'm not familiar with how they work), and unit feats that can embed into some of your troops to give them bonuses. The mechanics you are looking for is implemented with HQ stratagems (posture). It is implied that by setting a posture stratagem you can order your units to behave a certain way in combat.

I wonder if motorized units with infantry (eg Truck or APC) might have longer lasting supplies because they can carry more onboard?

No bonus to supplies due to trucks.

[Soar_Slitherine]

APCs can also reportedly block hits for subunits they transport, and subunits that are considered backliners (such as artillery or AT guns) are highly vulnerable to broken-through enemy units, which means they need frontliners to screen them, as enemy subunits auto-breakthrough if there are no frontliners left.

That about covers it for explicit combined-arms mechanics in the game. Tanks need infantry support in real life, but in the game, combining both in the same formation is not generally a good idea, as plenty of weapons in the game mow down infantry but can't scratch tanks, so sending infantry with them in the same attack often just results in needless casualties.