I know a guy who's clicked into the T'Wolves. He says the thinking on Tyus out of Target Center is that his ceiling is as a good back-up PG in the NBA. They don't ever see him being a starter. They think he can develop over 2-3 years into that type of player, but he's not good enough yet.
Basically the way it was explained to me is you have the guys who are so athletically gifted that they can get by on talent alone for a while (think Levine) & you have the less athletic guys, who get by on experience & out-thinking their opponents (think Rubio). Tyus is the latter, but without the experience and court savvy at this time. My friend said fans who think Tyus is going to be our next PG or should be playing a lot are going to be disappointed.
That said, there was no reason for Tyus to stay at Duke. He got his guaranteed money as a first rounder so he's getting paid to study basketball, which is what he was at Duke for, but without the paycheck. He wasn't going to learn to be more athletic at Duke. The weight room, working on his jumper, learning the tricks a savvy PG needs to know...all that can be done with the Wolves while he gets paid for it.