I've only just found this thread, but here are my experiences, for what it's worth....
I had a bilateral TKR (two knees replaced) just under four weeks ago. I was told it would be tough having both done together, but I was out of hospital in four days and bending my knees further by then than I'd been told I'd ever be able to bend them again. I ditched the crutches indoors within a week (apart from stairs), and now only use one out of doors. I can climb into a car normally, and I plan to ask next week if I can drive - I too was told six weeks, but I can't think of a single good reason why.
Ok, two knees is different from one hip. Also, everyone is different. I was pretty fit, and I exercised like mad from the start, right after the anaesthetic wore off in fact, and I think this made a lot of difference. I was up and walking with a frame the day after the op. The physios couldn't believe my progress, but they were used to people who lay about and moaned.
I still get very tired, and I wouldn't like to try flying yet - in fact, I haven't even considered it due to lack of work and money problems. However, lack of stamina has always been a problem for me, so this is nothing new. And it is less than four weeks!
The point I'm making is that everyone is different, and what you get told may have nothing to do with how things work out. I know quite a few people who've driven in less than six weeks; there are no absolutes in this. I can't make the decision for you, but maybe this will help a bit.
Last edited by Whirlybird; 2nd August 2012 at 19:48.