No I know this, its just that you should not have to use the reins at all. Or to as you put it, "Complete the circuit". I am just saying that I would much rather have my horse collect naturally then have to engage his hindquarters and use the reins to complete the circuit. He should do this already without me asking. Just my two cents on the matter. I do not mean to insult or offend anyone just wondering what others opinions are on collection and simply stating what I believe is true collection and how it should be.
I'm not sure what discipline you ride but isn't controlling the level of collection kind of what training horses is all about? The horse can't read your mind, you have to ask.