Is there any way of knowing the rate at which players become fatigued? Is fatigue earned differently depending on what the player did on the previous play? Is fatigue influenced by possible-injury rolls? If my QB just hands the ball off, is their fatigue going to be same or worse than if they threw? Special teams! Presumably also add fatigue to a player. More? Less?

Anyone got anything to remove some opaque from fatigue?

Fatigue is updated for each player within each moment of the sim - based on conditioning + what activity the player is involved in. If he is on the sideline, his fatigue recovers; if he is running a full sprint it reduces. Through the game, based on his conditioning, his maximum recovery slowly decreases.

Thanks JDB.

Does some players have more energy than others?

My WR/RB Lester Miller seemingly have much more energy than my other RBs.

Hes a reserve so perhaps the players he's facing are a bit tired when he gets touches. On top of that he's your strongest so he'll drag defensive players the best. Also, he's the most intelligent . Combine that with 100 carry and him being your best route runner of the bunch makes him the most effective at getting the handoff or pitch quickly and finding the hole. 88 speed is enough . Not a game breaker but a perfect 3rd down back .

Well. Jose Williamson is 93 to Miller's 97 strength. They're similar type backs, yet Williamson never run the ball as much as Miller.

Just did some stat surfing;

9 games played
Lester Miller: 269 plays, 97att/469yds/4.8
Dwayne Christie: 252 plays, 69/275/4.0
Jose Williamson: 173 plays, 43/189/4.4

97, 40-something, 93 strength

JW is typically my #1 back, Booker Reiss 2nd and DC and LM 3rd and 4th.

I've changed it around a bit, but even when LM was deep down, he ran more than the others.

Sounds great! Now the next question is how exactly does the game handle substitutions? Yeah I see the sliding bar with numbers but that's not an example. If its the very first play of the game and my WR takes it 75 yards or 65 running yards for the TD fully conditioned, how fatigued is he etc, what about the players chasing him on defense?

In the NFL generally speaking, almost always.. the offense is trying to stay on the field as long as possible to specifically wear down the defense, not themselves. The offense is controlling the pace of the game and the pace of substitutions in such a way as to trap the defense with the wrong personnel on the field. This creates mismatches and keeps players winded on defense. RB's for sure do NOT fatigue in the NFL for this exact reason, and it seems as though here the offensive players are fatiguing equally or faster than their defensive counterparts.

If my starting LT gets fatigued and is replaced by the backup, at what point in the drive does the starter go back in? When he's fully recovered or partially recovered? How much does each play generally fatigue a player at a any position? This is the kind of information players absolutely need to know because if not knowing these things, hidden fatigue ratings, hidden overuse triggers etc, can cause 7 interception one game and 5 another game or 3 starting OL getting massively injured in one game.. they will never be competitive. I really shouldn't have to be learning about these things in the middle of someone else's thread.

Offense rotates, but has the benefit of knowing what's going to happen, which is how they can trap defense and fatigue them.

Obviously RBs, for example, are more tired during and after the game, than before.

It's harder to chase someone running from you than it is to run from that same person. Its easier to change direction than it is to read a change and react to it. If a defender knew where a route was going before hand and could run straight there without having to shed blockers, defense would fatigue at the same rate as the offense irl. I know this doesn't answer the op question. Just elaborating on Lamba's comment.