Three people figured most prominently in the development of the knowledge I have about pool:
Dad
My father introduced me to pool at a very young age, and I was sweating matches of world class players by the age of eight. In February, 1969, when I was about to turn eleven, my father bought a Gold Crown I from his friend Mike Eufemia, and he then taught me how to play. I probably played 2-3 hours per week with my father from 1969-76, all of it straight pool.
Jack Colavita
I began driving in 1976 and, during the summers, I went to the Golden Q in Queens, NY, five days a week, always in the evening. I became quite close with New Jersey sharpshooter Jack Colavita. The Golden Q wasn't Jack's home room but he often came by. I often played straight pool with him (back then he went to 125 while I went to 40 for $5 a game, and he had a one-inning win on a few occasions). Though we were betting, Jack always taught me things as we played, and he taught me much of what I know about straight pool.
Irving Crane
I saw Irving as a kid, having seen him play on a few occasions, but had never met him. At the ACUI straight pool championships in March 1978, our paths crossed again, and I took the trouble to introduce myself, noting that I'd watched him as a kid. He was very friendly and a close friendship was the result, one that last for about eight years. In particular, we spent lots of time together during the PPPA World Straight Pool Championships over the years. Irving loved to talk about pool, especially defensive and tactical theory. and sensed my enthusiasm for those subjects. His classy demanor and style impressed me greatly, and nobody had a greater influence on the way I conducted myself at the pool table than Irving.
So, who taught me the most about pool? Was it dad, Colvita, or Crane? The answer is none of them. Most of what I've learned about pool I learned by frequently attending pro events, which I've done for over thirty years. I've surely attended pool tournaments in twenty five different cities, and have taken notes on the play for years. My guess is that I've watched tens of thousands of hours of pro level play live. There is no substitute for watching the pros, and the ones I've watched for all these years are all, to be fair, mentors of mine.