Yes I do. I really hate when people say it can only be shot on a tripod because it's so big. With a strap it's really not that bad. Yeah it's heavy, but you know that, and you don't complain because that is the sacrifice you make when you decide to do it. Some people shot with it only on a tripod, but some of them need to stop telling others that it can't be used in other ways.
I carried it around Chicago for a day with the metered chimney finder (probably 10 lbs now) and without a strap. My arms got a workout, but it was worth it. I got some awesome photos on huge negatives. I bring a tripod when I can, but if I can't no big deal. I use it when I want to, and I try to overcome it's limitations. I have been bringing it to sporting events (basketball and gymnastics), shooting with longer than normal shutter speeds for sports, because I wanted to. I am going to process the negatives today, hopefully I have captured some nice motion.
Sorry about the long post. It really bothers me when people say it can't or shouldn't be done.
P.S. I am not a huge guy. I'm actually really skinny.