The point is supposed to be that magic=/= thievery. By limiting the speed at which you train wizards you allow magic to be extra strong and dictate a tempo/breakdown in the game.
Now PERSONALLY i disagree with that concept, but geting wpa pumped quickly would allow for people to have "new" interesting concepts. For example noobium saying that his dwarf core would be on 4 wpa, i'd laugh at that with a high wpa mystic to cast ops and a low wpa core that can massively out-chain him. Dump on the correct dragon and his whole kd becomes insanely weak. My only suggestion to you is when you build a setup make sure it works without needing 1-2 key people on really good wpa or your going to have a hard time.