That was about how mine occurred--top of the hill, wanted a break, come to a stop, oops, suddenly can't get that foot out. Why I didn't just pedal forward is beyond me.
It took a couple of hours before I noticed a huge gash on my arm. It helped explain why so many people looked concerned about when I stopped though. How I gashed the arm on the other side of the fall is beyond me, though.
Worst part was, almost did a repeat when I rode through town in traffic later on. I (wisely) decided to not ride in the clips while there...