I'll talk about it with more depth, but I feel like the Y button thing is probably just personal preference, doesn't really mess with the functionality to me (except perhaps to enter and exit post post play in an easier fashion? -- I can't remember if you just press Y again to get out of post play). The post-game itself is the part worth talking about rather than the single button to initiate for me. I never really use signature gather, so I didn't even notice it wasn't on Y -- but it would make sense if post-up is there now.