An aside...
In "Principles of Psychology", William James made note of the fact that some adults can "visualize" while others can't.
By "visualize" he meant literally see a picture when imagining something.
He noted that children can do that, but the ability is lost in some adults.
In general, artists and poets and the like tend to retain the ability. Engineers and scientists and the like tend to lose it.
Robert Pirsig in "Zen and the Art of Motorcycle Maintentenance" would say "Romantics" tend to keep the ability and "Classicists" tend to lose it.
As a "Classicist", I have lost it. While I can clearly imagine a scene or a procedure or a part or whatever, I cannot literally "see" it in the way others can.
But I have noticed that when taking codeine-based painkillers, suddenly I can "see" things I'm imagining. Like it drops a barrier or something. I can direct cartoons, almost on my eyelids, so to speak.
Why am I mentioning this? Because the images do tend to float up to a point above and between my eyes. It can start out as a generic "glowing spot", pretty much exactly where a third eye would be. It can then be manipulated by my imaginings into images or even movies.
Hence, its easy for me to see where someone in a relaxed, suggestible state could start to "see" from that region, where the third eye would be projected to be.
So, visions seen by that third eye would be interesting, but consistent with my experience and not worthy of note unless they "saw" something not explainable by imagination.
Sorry for the hijack - back to musings on Scorpion's Spiritualism!