Originally Posted by
Domaje
I have done some more tests and the results are surprising. I merged 2 units with high experience (3 silver chevrons for both of them) and the retraining cost was never the same. When a good numbers of the veterans soldiers where not in the depleted unit, with the unit losing a chevron, the retraining cost was more or less halved. But even when the whole unit had the same level of experience, it was never the same cost from one test to another.
So I think that when retraining, the game keeps tracks of each individual soldiers, and that you pay for the experience of the new recruits that fills the ranks in order to avoid losing a chevron, unit wide. The higher the experience of the whole unit, the more you pay, still the higher the number of soldiers of that experience level in the unit the less you pay (relatively).