For the record, DMT is absolutely nothing like dreaming, and I find it very unlikely that it's involved in dreaming in any way. Psychedelic trips can be controlled to some degree when you're still in control of yourself, but not at high doses, especially not with ego loss. Since the latter is pretty much all DMT is used for... you're out of luck. Also, just in my experience, even the level at which other psychedelics are controllable doesn't allow for much control with DMT. It's concerned less with you and more with its own plans.