Well, I put in a lot more miles then most people. I carry a chain tool and have had to use it once on my own bike. I have seen other people break chains, oh about 3 or 4 times.

To give you an idea, in the same span of experience I have had more flats then I can remember, maybe over 100 and I have seen at least as many from other riders. I do most of my miles solo by the way.

So can you get away without a chain tool? I think so.