Practicing free throw shooting does work for the most part. The fact that we only talk about huge, athletic specimens like DeAndre Jordan, Shaq, Howard, etc. is proof of that. Anyone else besides a freak of nature would have been screened out from the league if they couldn't hit a wide open standstill shot from 15 feet at a reasonable clip (aside from 7 foot, end of bench stiffs like Chris Dudley).