The time before he played a game at UNC? I remember his first few months being terrible and people questioning him being a #1 pick. It wasn't till the second half of his freshman season that he started to get anywhere near the rep he had coming in.
You know why? hint :
Kendall Marshal
It doesn't surprise me that Barnes is having good workouts, he tests and showcases well. Its why he was picked preseason AA before ever playing a game in college. Same here. In competition with equal or greater talent, he has struggled.