Re-train re-group.
You do it all, but regrouping/retraining allows you to preserve and build valour quickly.
Say you have 5 jinettes that all went to valour 3; each has 2 str points_merge to a 10sp unit of val3 and retrain for the rest. If you do this consistently, your units will become better faster.
Re-read the post and think I missed the point :p
If you have time re-equipping old units is cheaper _ no increase in maintenance cost.
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