Very very interesting!
Thank you for sharing your enormous amount of knowledge and work on these investigations and graphs!

Ulf Rathsman's programs use the same type of heuristics, but change evaluation for each move/ply like the Expert and later.
Maybe that's why the MM II outperforms the SC as I see in an ongoing thread in this forum, despite MM II's worse handling of pawn structures?
(https://www.schachcomputer.info/foru...ead.php?t=6837)
(Pawn structures were not treated good until the last Rathsman, the Plymate Victoria.)

Maybe Schröder did the same!?
You can browse his algorithms at https://web.archive.org/web/20120320...l/prostuff.htm

Feels like a pawn structure test in the "Khmelnitsky test" suite would have been interesting! ...