Once more, I am wondering if your inability to walk through the wall stems from a conscious reinforcement of the notion that it is impossible to walk through walls because it does not work that way in our world. Perhaps in a state of semi-consciousness, this constant mind-enforced idea of physics is mitigated somewhat, since physics and its natural knowledge is subconsciously programmed to the point where it isn't a conscious thought to us, until confronted with the active prospect of just spontaneously achieving flight or walking through a solid object, at which point the normally passive subconscious rule springs into conscious thought.

I also think the "conscious reinforcement" is what maintains natural physics in dream state. I see the point of the "loop of personal control" but I don't know if it is that easy. although I have slight recollection of having been able to maintain flight in some cases as a teenager when dream flight triggered lucidity. but in most cases where I simply became lucid randomly, I'm usually unable to do anything beyond natural even though I'm aware it is a dream. Maybe I need to reinforce the idea that dreams have separate realities and maybe that could change how things work out.