I would've rather seen more of a mix of inside and outside training. He obviously still needs outside training, but my personal opinion based on training a couple high potential bigs from the beginning is that that is best chipped away at year by year. I did the same thing with Hall, training him almost exclusively outside for almost two seasons and in hindsight don't think it was necessarily the right move.
That said, the new training algorithm purportedly awards more balanced players with a slight bonus (something I've seen with Hall's training actually speeding up a bit), so perhaps he was right to train as he did and I've over-stated my disappointment. Doesn't really matter now, I guess - somebody with a good trainer pick him up!