Keep the wrist, hand, and fingers quiet adding nothing. They are used simply to complete the motion and send the ball to where the arm points, a fixed distance. The result will be a quicker, higher, and more effortless shot that comes down to a larger target, a larger landing area. And it will come down more softly. That one instruction will do wonders for shooting.
Most coaches feel fairly confident in their ability to teach shooting skills.
If their teams shoot well all the time I can't help them. I can only congratulate them, but the majority of teams do not shoot well only in streaks. Look at the height of your teams shots during practice, shooting practice, or during warm-ups. If the balls are just getting a couple of feet over the rim you are in for problems when the pressure is on because these flat hot shots have a small window of opportunity. Watch also to see if the shot motions are complicated.