On Tuesday, August 11, 2020 at 11:26:40 AM UTC-7, Joerg wrote:
On 2020-08-10 18:49, bob prohaska wrote:
I found this not-entirely-ancient video,
https://www.youtube.com/watch?v=KUEaN9FKGLE
which posits that there's no efficiency gain
using clipless (or traditional toe-clips) in
terms of rider performance.

That's a considerable surprise. It certainly
_felt_ more efficient to use clips/straps,
and then Shimano SPDs, compared to flat pedals.

Am I a victim of self-deception? Or worse yet,
marketing?

There is something to it. When applying force also in the pulling-up
phase you are using muscles in your legs that you wouldn't be able to
use with regular flat pedals.

However, my limit aren't the leg muscles, I simply run out of breath on
a long steep climb or when "flooring it" on a bike path that has no
speed limit. Long story short I used to ride with loop pedals which
offer the same "pulling up" advantage as SPD and similar. When I
switched to MTB flat pedals I found no difference in my performance when
it comes to average speed.

As for slipping off the pedals I never found that to be an issue. I have
to use them because I ride with sandals most of the year. So I did
something that makes purists cringe, I mounted MTB pedals on my road
bike. It's the lower cost plastic kind because those allowed me to cut
and then round the spikes to about half their length. This reduces the
wear on bottoms of shoes and also the gashes in case I crash hard.

--
Regards, Joerg

http://www.analogconsultants.com/
Yes, but it all comes from your lungs and circulatory system which is the limiting factor. A circular pedals stroke allows some of your muscles to rest while others are working. This is only a SMALL but important effect for professional racers.