Indeed. He clones Marshalls with tweaks. And the original Marshall circuit was a clone of a Fender. And Leo started his company straight out of the RCA tube manual. I think tube amplification was invented by De Forest (he was great as Dr McCoy in the original Star Trek series, lol).
I don't understand the attitude. I was telling a close friend about this thread, and he reminded me of Dr Z's better approach. Z profiled his own stuff and made the profiles commercially available.
Time marches on. My only lament, is that I cannot work under the hood anymore.