oops forgot to add this one thing that I find to be an advantage to clipless---diff muscle use.
I find that by varying my pedal stroke, I can give diff muscle groups a little break, and just like switching around hand positions is good for neck, back, wrists--by "pedalling" differently, it can be easier on my legs overall after a long day cuz I can change which muscles are working more. The "scraping mud off shoe" motion uses lower calf muscles more, so can give a little break to the "push down pedal" muscles.

any others find this?