We saw improvement from Reke in season with the shot doc, considerable improvement towards the end, although it's never admitted around these parts, so I'd at least be optimistic we'll see an improved jumper next year, after turning down Team USA to stay home and work on his shot.
BTW, shooting isn't about jacking up a shot per second for two hours, or whatever you're getting at. It's making sure the form is correct, which is damn hard when trying to break old habits. Then it's slowly integrating various moves, then pulling up for the jumper. As in, cross left, shot. Cross right, shot. Cross left, step back on balance, shot. Cross right, step back in balance, shot. Catch, pump fake, two dribbles to the left, shot. And so on.....gradually increasing the speed until you can mimick game situations with correct form.