I am ashamed to admit I do not understand what he said the data proved
The explanation was not as clear as it needed to be.What he needed to do was methodically build his spreadsheet and then let the spreadsheet tell the tale.
Just the demeanor and tone of voice was persuasive, tho - I didn’t pick up any vibe that he had something to hide. As he noted, you could go over the video as many times as necessary to be able to critique his point.