I was hammering hard this morning trying to catch some traffic in front of me. I was out of the saddle, en danseuse, when suddenly both of my feet flailed away from the pedals into nothingness. Remember, I was out of the saddle. Though quite a bit of my weight remained on the handlebars, I landed -- hard -- on the top tube.
I didn't crash or otherwise lose control. But I still experienced pain from that mishap today. And I never did catch that traffic.