Different SG's have diff interpretations of this period, and how "Hermetic Theory" (as opposed to "Blastum's theory" and "Thulsa Doom's Theory" and "Tim's Theory") came to be, but personally I think it's clear that he had to have sampled from more than just The Founders, even if not all those samples made it to the final format.
What he did was to try to find a GUT for magic, and to do so he would have studied as many different and disparate magics as he could.
Here's a related thread that you may find inspirational. The Order of Hermes, Early Recruitment - #10 by Cuchulainshound . Knock yourself out. 