I think that you're missing the point Gertrude.
The constant aspect glider circuit, which is pretty much also the same as is flown by the military in most countries, does make it much easier both to space different speed traffic, and to make the runway if the engine stops at most parts of the circuit. It is also much easier to accurately control the touchdown point, particularly where you are flying an approach and landing without power (which isn't a bad practice powered in an SE, but obviously essential in a glider).
When I'm not sharing it with anybody else, I fly CA circuits in powered aeroplanes as well. I wouldn't go so far as to say that powered circuits frighten me, but I don't like them and won't fly them when there's a choice.
G