Upon levelling up to level 21 (power description: You are so skilled at using melee weapons that skill training costs are reduced by 15%), my skill in 2H axes went from 10 to 22. It's also odd that it's level 21, but either way, it's totally broken. That's +43 to hit, +33 damage, +4% crit prob, +3 crit mult, and +4 DV.
Additionally, it seems to sometimes fail to apply (I have a Barbarian 3, Monk 3, Fighter 21 that got no skill increases from getting to level 21). That is, it fails to update until your skill level increases again.