Hello Jim

I don't really have any objective answer to your question, and I think that you're looking for more of a scientific than subjective answer - but all the same

I'm a fairly retro, tourist type cyclist, and a latecomer to clipless pedals on my 1995 tandem and 1990 solo.

What I have felt, though, is whenever I tell myself "stop pushing, start pulling" my bike goes faster and my quads stop burning.

Used to do the same with clips and straps - but to a lesser extent

Just offered for what it's worth - maybe nothing!