Q: Ok I am starting to understand your meaning about the Pure Release Distance (PRD). I have one question though. If I have the same release each time and I am really close to the basket like 4 feet away, how am I suppose to adjust my shot so that I won't end up airing it? When I am that close, my shot will always be strong.
A: If you're just 4-5 feet away and doing a "jump" shot under pressure, raise the Set Point so you're not so powerful. That way you can still shoot "full out," but you're weaker, your pure Release goes shorter. You can also hesitate before you shoot, catching only maybe 10-25% of the leg power, which gives you some stability, which works because you have a high margin for error when in close.
Q: Also, could I practice PRD shooting with free throw shooting?
A: Yes, but you're practicing the "pure" Release, not the PRD. That distance is where you can drill shot after shot with no legs (or a minimal, constant amount of leg power just to trigger the action).
To do this, go to a distance a little beyond the PRD (say 6-7') and do a miniature free throw motion. Call it a "micro" free throw. The leg drive is more than for the PRD and less than for a full free throw but the Release is the same. Learn to use the leg drive (in this case, just a fraction of the real free throw distance leg drive) to drive and trigger the shot. You can say it's just another way to practice and master the Release. Note that the body motion is a "Down-Up" motion, starting from a straight-legged position. This is a powerful, stable way to shoot, unlike the crouching method, where you start from a bent knees position. The crouch takes away almost half of the powerful down-up action that will help stabilize the shot, so I recommend against it.
With the Release full out and high, you will find the perfect arch for each distance and leg drive and start to drill shot after shot ... swish swish swish. Then move back further (maybe half way to the free throw line) and call it a "mini" free throw and do the same thing, now with a bigger leg drive. Train yourself from there, and then further back again until you reach the free throw line. The leg action triggers everything and stabilizes it; the constant Release puts the ball into high orbit to the center of the basket. You'll find these will start to become automatic, because of the full-out Release.
Proof that the elbow needs to be to the side ... a little
I don't believe in the "Elbow under the ball" theory. I believe you shoot best when the center of the palm is pointing directly in line with the basket. That's where the ball is. With palm directly in line, you have the strongest hand position. In that position the elbow is NOT directly under the ball! In fact I feel elbow-under-the-ball theory interferes with what is natural.
Here's the proof:
This can be done anywhere. Pick a target, whether it be a basket or a spot on a wall, sitting or standing. With or without a ball, let your stance (or sit) be "open," turning your body to the left (for right-handers, right for lefties). Now bring the shooting hand above your shooting eye and in line with the eye and target. Point the center of the palm in line with the chosen target. This gives you the strongest hand position, with the most fingers behind the ball.
Now look at your elbow. Note how it is to the right (for right handers) from 3-6 inches, depending on the length of you arm. If the hand faces directly in line from eye to target, the elbow has to be off to the side a little. It's not way off to the side. That won't happen if the hand is in alignment, but it is to the side some. That's the way our hands, wrists and arms are built
Now bring the elbow under the ball. What happens? Do you see that it tilts the hand off the target? Isn't that a weaker position for the hand? Sure, you could shoot that way and the body would find a way to propel the ball forward, probably by rotating the hand a little, but it's not as secure and solid as having the hand directly behind the ball.
With the center of the hand in alignment, ACCURACY occurs when you push your arm directly in line toward the target ... if the wrist and hand are relaxed and do not throw the shot off line.