Great question, and this is a code I've been trying to crack for years, unsuccessfully.
Here's where I'm at:
I'm in ATL and just finished WK5. I landed on what I feel is a really nice baseline FAT level of 85 with some subs that are giving me (most of) what I want.
I have HB/DL/EDGE set at 80-83 and everything else default.
What I saw is my larger guys starting to get a bit yellow on plays 5-7 of drives, and maybe even needing to rotate out for a play on 10+. I was seeing clock stoppages vs. clock eaters having their proper effects, and I was not seeing disappearing players.
It took some chutzpah to move past 75, which is my normal threshold, but I made it to 83 as a test, and it worked out, which tells me my original idea of 85 is probably it.
What I'm gonna monitor is how the sub levels look as the year progresses.
It seems like this game has progressive fatigue running the whole time but not really running--it more so seems like it arrives in bunches, maybe at WK7 and then again at WK12 or so. So with that, we'll see if GM 6 vs. SF looks normal or if players start disappearing.
What I'm anticipating is keeping the same FAT value but walking back the sub in/out values according to what week of the season we're in. My gut says around WK12-13, you go from 80-83 for your HB to 77-80 or something like that.
In any case, I'll stream my games here:
https://www.twitch.tv/roguehominin, and I try to play good, sim football and engage with the folks who stop by.
I'd love to have a conversation partner on this issue, as I think it's a code that CAN be cracked, just with the right folks. Getting this mechanic working is my white whale in Madden, lol.
I should be able to play one in the early AM, and if not then, certainly after church, around 11 AM. I'll look forward to seeing what these values yield.