I've read all this before. I can tell you I started out with a still flywheel and crap you say they use on brakes. The steel FW will warp with very little slippage. 20 years ago, I was still stuck with a steel FW. I could get 6, maybe 8 passes out of a disc. I had 3. One in the car, one on the way back to Ram and the other at the shop, ready to go in. 20 runs and I had to surface the FW.
When I finally went to sintered iron, I could wear out a disc (150 passes) and throw a new disc in a go. The aluminum FW didn't warp.
So we must live in alternative worlds. My experience doesn't match your theory.
I stand by using the lightest FW most guys can find, and that's usually 11-15 pounds. That's plenty when you add in the disc and pressure plate.