What's the safety impetus for junior bmx riders to not be allowed ages 12-under to use clipless for racing? They claim it's to develop "skills" you'd otherwise not develop.
OK. That's not really a thing in cyclocross where you hop barriers, fly around muddy corners, etc....... So given a similar application the rules rationale falls short it seems.
Reason I brought up bmx, is the over-12 year old elites are allowed to use them and they do use them. So folks who used to say "well bmx sprinters don't use them" is kind of a bum argument.
For casual riding I don't find it relevant at all. For really giving it the beans, yeah, it helps. I think the bigger loss is that if someone chooses to use a squishy running or fitness foam shoe. Even if the loss is 10w (random number), 10w out of a person only putting in 100 to 150w at a casual pace is a very large % loss.
Even run racing shoes now have carbon integrated to them (vaporfly's).