Hi, David. I essentially agree with your position (though I give myself and the Mona Lisa photographer a little more credit.)

For purposes of this discussion, I look at the issue as a kind of puzzle (as opposed to an actual legal or ethical dilemma.) The "solution" being: you get to publish a new piece and take author credit. How would you do that, here, what else would you need to change?

Right now, the derivation is too direct. A plaintiff's lawyer would create charts showing the vertical mirroring and show them to the jury. So, you need to change things around, either creatively or algorithmically.

Encrypt the original piece, so to speak, where the cyphermusic is itself rendered as music.

Thinking about so-called "designer drugs", it's a similar puzzle: What do you need to do to this illegal molecule to be able to sell it in gas stations? Which of course has on its flip side the "law and order" puzzle: How do you define what you're banning in such a way as to cover all these tricky molecular variations without also banning sugar?

That legal challenge is the challenge of defining what philosophy calls "essence": that which cannot be changed about a thing without it ceasing to exist as that thing.

So, what is the "essence" of "You Won't See Me"?

I think it ultimately has less to do with musical structure than it does with natural causation, but I should stop.