That's extremely interesting. To see that even with an all time great shooter like Nash there is a pretty significant disparity between practice and game is eye opening.
It's pretty simple, really. In practice, you get into a rhythm, because you are shooting much more without stopping. Nash's numbers prove that taking 2 shots at a time throws your rhythm off. I used to practice free throws under HS and college rules of 1 and 1, to try to simulate some type of pressure conditions. I'd shoot 50 1and1s, to see how many points I could score. The highest score is 100 pts, but if I miss the first of the 1and1, I lose the opportunity to shoot the second. I then would treat my final score as my effective percentage.
If you can't play defense, you can't avoid that. Just because you can do it in some cases doesn't mean there's any underlying reason you should just be able to avoid anything you're not good at. This is reasonable logic. If Shaq is going to dunk on someone, people grab him to stop him force him to make free throws. That's fouling people intentionally for the purpose of gaining an advantage yourself. Why aren't we trying to eliminate that?
Free throw shooting, for some people whose hands are at rim level upon release, is not easy. For some players it's akin to asking the pitcher to bat. For someone like DeAndre Jordan, it's an entirely different sport than the one (rebounding, blocking shots, high percentage shots) he plays the other 95 percent of the time. It's like asking Jordan Speith to roll the golf ball into the hole once he gets on the green.
Fouling the player without the ball is treated completely different than fouling the shooter. They have different penalties and different rules. And they always have. Only recently has a loophole to use the bonus situation to your advantage, started (against a player who doesn't even have the ball). It's a BONUS. It is and never has been intended to give any advantage to the defense. Just like football can decline a penalty assessment, the NBA can allow declining the foul in the BONUS situation, when the foul is against a player who doesn't have the ball. There is no reason to protect that loophole when it really is not a basketball play, and it drags on the game. Hell, even the NCAAs got rid of the one and one bonus, and replaced it with two shots regardless if you missed the first.
