Where are you getting 37% shooting? He's shooting 41% from the field over three games. But that's deceptive too, because his true shooting is elite for a guard at 62% (largely because he's shooting 43% from three and drawing a lot of fouls). Thornton's SL performance so far has been about as good as you could ask for from a 2nd round pick IMO. Playing well in Summer League doesn't necessarily mean much, as we saw with Cam Whitmore, but you'd still rather a guy kick ass than play badly. Eye test for me, so far he looks like he could definitely play bench minutes in the NBA.
He said that before the stats page updated, I think. That said, FG% is such a horrible stat because it assumes three pointers are worth as much as two pointers, and free throws count as nothing. TS% is not a perfect stat, but so much better than FG%. Eye test easily says Thornton was scoring efficiently and he probably should have known that number was going to rise, even if it was a bad number to make a judgement on. On whether he can play bench minutes, assuming bench is more than garbage time, I'm just not sure. It is really hard to judge which small guards adjust to playing with bigger and more athletic players on the court and which ones don't. For me, he's got to be able to get his 3 point shot off versus NBA closeouts frequently, and at 6-foot tall, I'm always a hopeful skeptic.