10 percent of primary training is given to a random skill.
Please understand, I am with you here. I'm not liking the changes. But you have to read a bit more closely. It says the average player in the game will train 10% worse, with the other 10% going to a completely random skill.
That's only the average player. It also seems to explain that, for a player with all equal skills, he will train just about as fast as he does now (I assume that means no random training, too).
Still a very weird system.
Run of the Mill Canadian Manager