Originally Posted by
cyccommute
I assume that somewhere in your education you had to take physics. What makes you think that your shoes are going to do any better job of keeping you from falling if you get hit, slip or fall? Sticking a leg (or arm) out in a collision, slip or crash does nothing to slow you down nor does it "catch" you. The least it's going to do is to cause muscle tears and the worst is a compound fracture that takes months to heal.
To paraphrase a great blue...um...creature: "Keep your hands and arms [and legs] inside the carpet!"
I recently had two examples on the same ride that reinforced my decision to use flat pedals, rather than clipless. It was 35 degrees and runoff from a storm from the previous day had created a number of puddles, some six inches deep on the asphalt trail. On two occasions, while riding very slowly, (I didn't want to get sprayed) the rear wheel slipped out from me. Very rapidly. I think the runoff had deposited a very thin layer of very slippery mud/silt. It was only ability to put that leg down quickly that stopped me from falling in that puddle. Being soaking wet on a windy, 35 degree day ain't fun....I was 15 miles from home.
p.s. I've had a physics class or two.