I have had similar experiences in regards to the recognition of locations of waking reality appearing in dream states with a modification. It's quite compelling to know that these dreams are essentially the labyrinth of our own mind, and in turn we stand face to face with the capabilities of the mind.
Also, the barrier in which you speak of. I've had one very bizarre OBE that lasted shortly and I barely "floated" out of my conscious body/mind whatever. As I forced myself to dis-associate I experienced a dial-up/static sound vibrating throughout my head along with some pressure and I found myself sitting up out of my body. I wouldn't say I physically came out of my body but psychologically I did in some sort of fashion. It was quite frightening though, so I kind of let go and returned.
Finally, one more anecdote. This was a brief lucid dream. I was in a weird and bare bathroom in which I was staring into a mirror. I saw myself and became lucid, but as soon as that happened my whole experiential reality became very unstable. It shook like an earthquake and the fabrics of the room tore apart and I found myself in absolute darkness. I was conscious still and after a few moments I felt the intuition to open my actual eyes and was awake in bed.
I have much more lucid anecdotes but would rather not throw your post too off point from your inquiries. This stuffs just way to tangible and perceptually "real."
my loopy guess is that t. mckenna is off hopping about hyperspace wielding a butterfly net analog, all the while collecting the most peculiar.