I distinguish between consciousness and awareness, awareness being what you call consciousness. So yes, it's essential to distinguish between the two. Basically it's the difference between the mind and the one who perceives it (in its entirety). However, I must really stress that that "primordial quality" or "essence" (which I call consciousness and which we refer to as "I", i.e. *the* subject) is verifiably without any qualities or attributes whatsoever -- all of them are what is observed and "your I" is the same as (completely identical to) "my I".

When I talk about the possibility of consciousness (your "witnessing consciousness") turning out to be an epiphenomenon, I simply admit the possibility of the observer to be a mind construct similar to ego etc. However, how could then trillions of different minds produce something that is identical to a T is beyond me (and clearly beyond everyone). It also begs the question of minimal neural complexity needed for consciousness to arise in such a manner as animals are obviously conscious too. But as I said in the article, this possibility is sort of an utterly inconsequential matter.

Furthermore, there's still existence as such (not "existence of") which is clearly an ontological primary. And on that "level" you cannot separate "I" from "am" as each implies the other.