I've seen his video about guitar tone. Very cool but anybody who has every played an electric guitar knows the acoustic quality of the instrument can be heard through the amp and it's influenced by the bridge, tailpiece, neck and fret material.
It's always the sum of all parts.
Not to mention the difference between a recorded tone and the actual tone in the room.
The point of his research (and no one can say that he doesn't put in enough work to justify calling it that) is to choose a claim that "everyone knows" is true and test it empirically, with clearly stated aims and a narrow focus. Watch the videos with an open mind, and you're forced to agree that at least some such claims begin to look weak.