You can't turn a doublewide trailer foundation into a mansion and still have the trailer be part of the final deal. I guess you COULD - but then you'd have a trailer in the middle of your mansion's courtyard.

Yeah, you can add chords to something, but it doesn't change the bones. If it doesn't work in its simplest form, adding more chords won't necessarily make it work better - it just serves to make the jazz musician say 'look - I turned it into a jazz tune!' Now... how does it SOUND? Norwegian Wood isn't a great example because the Beatles' harmonic prowess was WAY more advanced in a lot of ways than most contemporary pop tunes. It was already a great song without adding anything else - but what Herbie added, tastefully and very specifically, works well. The Beatles were still rooted in a lot of traditional harmonic concepts, with some unique twists... which is why their material is perennially fruitful for improvisation. That's where the whole 'writing something that will last for 100+ years' part comes in.