I'm assuming same reasons I would think Turcotte going back is bad in this case--less to do with the player and more to do with the program. It's a young team and the coaching/leadership appeared rudderless paired with the rumors about players 'only worried about their stats' or whatever. Not a terrific development environment.
Maybe less for Caufield because it's clear he was made "The guy" there from day one and allowed to do whatever the f*** he wanted, sort of like DL's criticism of Michigan, recruiting a bunch of stars then letting them run amok instead of 'developing' (Opinion). I mean do we think any single one of those Wisco kids is more ready for the NHL now than at this point last year? Maybe marginally. If it's one kid that's his problem, but literally every one of them has the same issue, from Caufield to Turcotte to Miller and more.