I have been extremely fortunate, and have spent a good bit of time with both Ron LaClair and Fred Asbell. They have both helped me in different ways. Fred really helped me define my personal form. He makes things like "release" so simple. Ron has helped me a GREAT deal with the mental aspect of shooting, especially under pressure (Ron has also taught me quite a bit about woodsmanship, but that wasn't your question).
Lastly, I honestly have to give credit to my Dad. Dad was probably the best and most dedicated bow shooter I ever met. He didn't get serious about it until about 1968, but once he did.....wow. He never competed, but he should have. I watched him make some amazing shots. He put a bow in my hand EXTREMELY young, and was a good, gentle, firm stickler on form. He turned me loose with a quiver full of arrows, and always made sure I had a good bow, properly tuned, and good arrows. He was also an incredible arrowsmith, and sold some commercially. Steve Turay recently located and gave me a dozen boxed arrows that my Dad made in about 1972.
I have had some good influences, and I'm grateful.