Maybe its the rebalancing of the combat to make it all about morale. Perhaps previously (I played 1.0-1.3 and 3.2 before 5.2) generals and terrain were relevant because you could take enough casualties to affect the result of a battle, but in 5.2 the only point of generals is to conserve your manpower pool.
There's plenty of other stuff that's changed. What happens when morale hits 0 and the stack wipe rules are different from 3.2. Those threads barely talk about morale at all, and casualties are irrelevant to battle results in 5.2. Its all about not losing your morale first and being able to stack wipe when the opposition loses their morale. Casualties are of strategic importance due to tight manpower, but they are tactically irrelevant.