Let's discuss the length of people's fingers on a scientific aspect. Yes everyone has different hand sizes. Having an index or a ring finger as long as your middle finger is an absolute rarity. To those that say that the index finger is "about" the same length as the middle finger. To clarify, these 3 pictures are the common finger lengths. The ring and middle fingers are actually found to be a little closer to the same size in an extremely rare percentage of people not exactly the same length but closer than the index.
If we were to say that a perfect middle finger release is a 100% then everything that is off from a perfect middle finger release then drops below 100%. So a middle finger and index finger can be a high percentage shot, it still is not as high as a perfect middle finger release because on a middle finger and index finger release your hand has to be placed precisely on the ball or you have to twist your wrist at the end of your release. Try and think of it this way. Would you rather have two separate forces (middle finger and index) pushing on one object (basketball) trying to make it go straight or one force (middle finger) pushing on one object making it go straight? I'm referring to the final end of the release. Obviously all fingers are pushing on the ball. The conclusion is one force (middle finger) because it is harder to control two forces (middle finger and index) as opposed to one.
There is no perfect form, but there is a perfect release and that would be a middle finger release. There is more forgiveness with this release unlike the middle finger and index, which leave minimal room for error. Shooting free-throws you have more time to think about your exact hand placement for a middle finger and index finger release. During game time it's easier to think about catching the ball as close to the center as possible using the middle finger release. So why not practice the shooting form that is more game related.
Go to my videos to see what finger some of the greatest shooters release with. Go to allnetshooter.com to find out more