Had a flat on the way home. A nail went straight through my Gatorskins and through both sides of the tube. Not much will stop that. One patch held, the other didn't, so I changed the tube. There are two pieces of good news:
First, my new Mountain Morph "frame floor pump" worked like a breeze. I had it up to 80 PSI in no time. It would have taken it further, but I was only a ten minutes ride from home and a real floor pump, so I didn't bother.
Second, in the twenty minutes I was stuck, four or five other commuters offered help. It's good to know my back is covered.