My son had a single speed commuter that could be flipped into a fixie.
He said "No f*n way."
That pretty much sums up my attitude, but of course, I am risk averse, compared to a lot of people. My non-riding/adventure friends don't think so, but I know my limits.
I do understand the allure of a single speed, but my body is kinda too broken down to deal with it at this point in my life.