There's some defense for the last shots many times. Defenses focus so much on Parker that it's almost habit for him to put up a jumper when the screen allows it. Pop, as we all know, loves to play percentages, and having Parker punish teams for going under is automatic, and will always, in the long run, benefit the team whether or not the shot goes in. Parker has also worked immensely hard to make that shot one of the most reliable in the game. It's easy to second guess the decision based on whether or not the ball goes through the hoop, but that seems like a practice that's ignorant of the way the Spurs have played for much of the last two decades.