I've been riding clip-less for about a year, the last 6 months have been on a fixed gear bike (brake-less). I have fallen twice neither times were due to not being unable to unclip, and both happened at about 10mph. First one was my first ever skid stop, in a warehouse. The second was on wet cobble stone, the front wheel washed out with out warning. I was lucky, the first fall, no one was around, the second only my riding buddy was there, we had a good laugh.

When I was starting to learn track standing, I would have to get out of the pedal in a split second due to my crappy balance at first. Came close to falling, but was always able to pop out before going to far over.

Lead with your heel.

SPD set up get lots of love from me.