It's also because I, or my body memory, hadn't remembered that I had to change technique properly. I've lifted feet off the pedals, forgetting that zero or minus weight on the pedal means no grip or no pedal......but still, in the clipless debate, every ounce of weight used to keep your lifting foot stable on the pedal is an extra ounce that the downstroking foot has to apply. A more experienced rider on flats would do a lot better than I did, certainly. The only disadvantage to SPDs that I've noticed is that, in my experience, is that they can be dangerous to drive in.