2011 and 2014 are the seasons he had injuries during the season.
2011
Under Kubiak, he missed the 1st game with a hamstring.
2nd game he had 10 carries in 2 quarters of work and then reinjured it.
3rd game he missed.
4th game he came back and had 30 carries, so that definitely wasn't a case of easing him back in.
2014
Last season under O'Brien, he had a hamstring in camp but was good to go by the time the season started and was a workhorse in the first 2 games before reinjuring the hamstring. Going into the games O'Brien had quotes like
"Arian's going to play a lot," O'Brien said, per the Houston Chronicle. "After that, we'll see how it goes." which he lived up to, 27 and 28 carries in those games.
Missed game 3.
Returned in game 4 against Bufallo. John McClain said, "Foster would't be active if he wasn't 100 percent. That means he'll get a full workload." But Albert Breer and Tania Ganguli both reported Foster's workload would be based on how his hamstring held up. After the game, according to Rotoworld, "Foster himself acknowledged he wasn't 100 percent in Sunday's win over the Bills, managing six yards on eight carries". Foster had the 8 carries, Blue had 9. So that would be a case of the team limiting his carries though he was playing.
Played through game 9 including 25 carries the next week against Dallas. Game 9 he hurt his groin and missed the next 2 games.
Returned in game 12 and had 19 carries. Blue and Grimes combined for 12 carries. That's about 60/40, close enough to a normal distribution which is more like 67/33. In games Foster played, Foster had 260 carries while Blue and Grimes combined for 128. I don't see any O'Brien quotes about their plans for him going into that game, but did find
this quote which might give some insight into O'Brien's philosophy and also fits with the bit from the Buffalo game earlier in the year when he returned:
"Soft tissue injuries, those are things that happen quite a bit. I would say in our time this year that we haven't had as many soft tissues as teams that I've been associated with in the past," O'Brien said. "You have to let them heal and you have to listen to the player about where he thinks he's at, and definitely communicate on those things."
So the game Foster said publicly (after the fact) he wasn't 100% for against Buffalo, he got just under half the carries. Don't know what Foster indicated going into the return week 12, but at least it doesn't show inconsistency by O'Brien. Of course, I don't expect Foster to indicate he's less than 100% if he plays, so maybe that only helps us a little.
By the way, to say things more clearly than I did the first time... the point my comment was trying to make is that it doesn't make sense to take a stance today on whether to play him or not when he first comes back. It should depend largely on what we hear from the coaching staff and from Foster at that point in time. I wasn't trying to say, "He
will be on a pitch on a count", I was trying to get across it is a definite possibility and we just need to wait and see.