Yeah, I'm very aware of his theory, but to be honest it doesn't quite make much sense. I'm not saying there might not be more possible when it comes to energy and influencing that, in the sense of a spiritual force or something mental / psychological.

But the idea of an unknown but very advanced civilization before the earliest life on earth known to us (as that is what it would imply), is very much unlikely. Most geological layers are known, layers that already disappeared into magma... well what could we possibly know about those? It doesn't make sense to speculate about or even downright assume there might have been a hi-at in evolution with a humanoid civilization in between all what is known.

Such a civilization would surely have left it's marks, let alone the huge gap between our current state of evolution and their supposed time they were around.