I think I get where you are coming from now and your thoughts do make sense. With the right sleeping pad it doesn't matter what position you sleep in.
I love my sleep pad (ExPed Synmat UL 7) and am out like a light (and tend to stay that way) as soon as I hit it. If you find you can't train yourself to sleep in a new position, try a different sleep pad that allows you to sleep however you want to sleep.