This assumes that you are using the standard Command hierarchy of Division => Corps => Army => Army Group => Theatre. Clearly, the effectiveness of traits at the Theater and Army Group level are severely diminished. If a Division commander, Corps commander, Army commander, Army group commander and Theater commander all have the Offensive Doctrine trait, it gives the division a combat modifier of 10% + 5% + 2.5% + 1.25% + 0.625% = 19.375%, when attacking. Meanwhile, while the Army bonus is lower, it could be passed onto 25 divisions. While this may seem to be the best scenario, this effect is only applied to a limited number of divisions. This means that, for example, at the divisional level the trait modifier is granted 100% to all brigades in that division.

Note that if you skip an HQ by for example assigning divisions to an Army, then the Army replaces the Corps effect for the trait.

Traits cascade down the chain of command and are halved at each HQ level: Generals can have distinct traits that offer various benefits on the units he commands, yet each effect is modified by the general's position in the command hierarchy. For example, if you skip the Corps level and assign divisions directly to an Army HQ, you lose the chance of a reserve division entering combat.

Note that if you skip a command level, the skill level effect does not change.

Division: Increase combat efficiency by 5% per leader skill level.

Corps: Improve chance of a reserve division entering combat.

Army: Increase organization by 1 point per leader skill level.

Army Group: Decrease supply consumption by 5% per leader skill level.

Theater: Reduce stacking penalty by 1% per leader skill level.

The effect of the leader skill level is a function of where the leader is in the command hierarchy: Leader skill levels, and their possible leader traits, have the following effects:Д®very leader in the game has a skill level. Leaders play a critical role in the command structure of an army.

Hearts of iron 4 leader traits