Sounds like a smart guy. Interesting that Usyk has been sparring with HW's for quite a while. Current estimations of Usyk's chances vs Joshua are based on his performance against Chisora and Witherspoon, the only HW's he's fought. I believe he defeated both men; that's pretty good. No, he hasn't looked like a Mike Tyson but that's never been his game.
CW boxers frequently use HW boxers to spar with and vice versa. Some LHW boxers frequently spar with CW boxers. It is relatively casual thing.
