I was fortunate enough to train with several on that list: William Aprill, Louis Awerbuck, Todd Louis Green, and Pat Rogers. (In fact, the photo of Dr. Aprill there is one I snapped of him while he was teaching at Paul-E-Palooza 4.)
There are a lot of elder statesmen in the training world who aren't going to be actively teaching forever. If you want to get out there and take a class with them, sooner is better than never.
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