Cause: Minions are applied stats, abilities, etc as they are when they are summoned. Changing your skill tree does not effect existing minions until they are resummoned.
Effect: It is possible to have several minions summoned that “break the rules” of the skill tree. Example: Spec 20 points into Skeleton Mage tree, selecting the “Archmage” node. Summon your Archmage, then spec out of the Archmage node, the continue to summon additional Skeleton Mages (which should be impossible with an Archmage).
This will cause balance issues in the future when the game moves to multiplayer.
Thanks for the awesome work you all do!