I'm not arguing that players can't improve their shooting stroke in the NBA. It happens all the time. In fact, Giffey's shooting ability isn't what I'm questioning (though I do wonder how he'll adjust to the deeper three point line). All I'm saying is, 23-year-old's who are naturally hesitant shooters usually don't transform into reliable NBA offensive players over night, even in a specialized role. For instance, I don't think Giffey is going to turn into a Danny Green type player simply by working on his stroke - there is a certain art to being able to hit contested, highly pressured shots that I think you either have or don't. Giffey's a tireless worker and he has a beautiful stroke, but I've never seen him explode into a shooting motion half a second after receiving a pass. That's a skill that I'm not sure can be taught.
Granted, perhaps I'm overselling the transition from college to the NBA as it relates to shooters. There are definitely players - like Shane Battier, for example - who are able to skate by on defense and limited offensive ability, but those guys are few and far between, and Battier was considered one of the best defenders in the entire league in his prime.
Is it possible that Giffey develops into a better shooter than he is now? Sure. Unfortunately for him, NBA teams aren't going to wait around and see like they would for somebody like Kawhi Leonard. They're going to watch him out of the corner of their eye in the summer league, and if he's not lighting up the nets from deep, he's not going to make a roster regardless of how good of a defender he is. Giffey has a shot at the league - which is more than anybody possibly could have imagined two years ago - and I'll be rooting like hell for him, but it is going to be a long uphill climb.