retrain question and exe?

[QuintusSertorius]

See, that's what I thought but I also read that the new green units are mixed in with the veteran units and the experience chevron adjusted to the average.

No, this is what happens when you merge units. I'm fairly certain I've seen a unit depleted to under 10 men be restored to full, with no loss of experience, if you retrain.

With rtw.exe, the AI never retrains, so it's effectively an exploit in favour of the human player.