He most certainly did not. Of all the different takes out there, his is very weak.

>Most recent music infringement lawsuits seem to argue that some combination of...

There is a very good reason: as he mentions, the chords diversity use in pop songwriting is typically so poor that based only on that, the amount of things considered plagiarism would thus be ridiculous. If the similarities affect almost all dimensions (style, arrangement, rhythm, melody, ...) to the point of being "essentially the same", then it's exactly what people would want the law to exist for.