There a whole of questions like this one that have not really been answered (Podcat sorta did for this) that have to do with "combat resolution" as well as "proper" or "ideal" division composition. For example, if a division lacks an engineer unit (or has one) what happens? Does it move slower (no one with skill and equipment to fix roads/bridges) does it attack entrenched or prepared positions less well (no one with skills and equipment to "take out" mines, pill boxes etc. Is the casualty causing number just added up from the sub units so the more artillery you have the more damage you cause (or do you have to have some ideal "balance" between infantry and artillery? Are the armored piercing vs armor protecting number significant as they were in TFH (I interpret podcats response as a yes on this one). Will their be significant combined arms bonuses like in HOI3 that need to be considered in building divisions etc. I would hope that the development diaries will address these kind of questions for air sea and land and also for air - land combat and air sea attacks as well.