...I do believe Eric had a point when he was speaking of experimenting with such events.
Well, it depends. If you guys experienced what I experience in that state, experimenting would not be encouraged at all. It's an excruciating sense of imprisonment in a malevolent limbo. You guys want to experiment, you are welcome to that, sorry I cannot take your invitation, lol.
That state happened often when I would nap in the afternoon and especially so under a hot sun. Also, it happened when I used to commute on buses, taking a pillow and earcuffs to sleep. In a few words, when sleep was not too comfy the likelyhood of occurance was higher. Although it happened when sleeping in the familiar home bed as well. Lately, it happens more rarely, I do not commute any longer, I sleep less, I'm getting old, any of these reasons...