I would never question Stanley's commitment or toughness. Quite simply put, I have no idea what he is going through. I know in my own field (systems analyst - programmer) I have encountered a lot of people and their "pain/discomfort" level. I've known people who will come into work with the flu (against everyone's wishes), and those who will call out with a hang nail.
From what I've read, Stanley's injury was messy and severe enough that retirement was at least mentioned. Talking to a medical buddy of mine he said had I suffered the same injury at Stanley's age, that at my age now, decades later, I would be walking with a noticeable limp and probably use a cane. That's how bad his injury was.
I've questioned whether or not he will ever have the strength he once had, and I do think it's fair to critique his performance once he returns, but I'm not going to say he's soft or milking it or whatever. I think that would only be an assessment I could make if I had a lot of personal contact with the man.