I am honestly trying to think this through, not trying to say 'you are all wrong'.
e or 5) I agree that a stranger has nothing to do with. But as a stranger I wouldn't be able to tell if it is a new limp or not, so I wouldn't comment to that effect anyway. This I really meant exclusively for someone I know, and know well enough to be able to broach perhaps tricky topics. And I would not go barging in: You need to see a doctor. Rather I'd say, I notice you are limping,(you didn't use to), what's up? Are you in pain?
Would that be wrong?
b) When I say I may want to offer help, I do mean it in the way you described upthread. I wouldn't go saying, 'hey you're limping, do you need help?'
When I was pregnant, sometimes people offered me help and it was clear that they were doing it only because I was pregnant. Although they never said a word, but they wouldn't have e.g. offered their seat to me if I hadn't been pregnant. So the fact that they did, made me feel a little self-conscious of being pregnant. Am I wrong to assume that when someone offers you help (as in, asks if you are in pain and would you like help with those bags), even though they never say a thing about the limp, YOU know that they are offering because they noticed the limp? So in effect they are 'reminding' you of it. Would you rather people didn't offer help, but waited for you to ask? Genuine question.