If you want to prove or disprove this, it is easy to use analytics. Score plays, especially plays in the first half and ask the question if UM had advantage in formation because UM was supposedly aware of the play call. I have seen no evidence pointing to that. I give the example in another thread which was the UM<>OSU 2022 game. OSU scored on their first two drives and was on the way to a third score when Day made a strange 4th down play. If what you say is true, the best time to leverage it at the beginning of the game. My opinion of watching that game was the inexplicable play calling of the OSU staff. I call it 4th and 4 disease. If OSU had run what they did against Georgia, they probably would have beaten Michigan. Yet Day refused to run Stroud, refused to run on and short, and insisted on cover0 everywhere on the field. Its okay to bend but not break and go to cover 0 in FG range.
Find a game in 2022, and show with the film that UM was playing 4-dimensional chess. I did not see that. I saw a lot of games where teams like Rutgers, Maryland, and Illinois hung around in the 1st half. Those teams were winning RPS.
I think that changing up signals is a lot easier than you think. My opinion is this Stallion fella had a knack for decryption and human nature. Signals probably get changed every week. But we all have tendencies. He may have been looking for patterns. If I want solid encryption I let a random generator set the standard. Stallion may have seen benefit in trying to pick up a humans tendencies to make it easier to decrypt during a game. I have no clue how to measure success. It should be useless if a staff does its due diligence. I would expect the PSU and OSU staff to have separate signaling for a big game. Thus my reasoning that I don't think Stallions work moved the needle.