GJM, do you think there's any chance having backup irons (maybe with a high-vis front sight) would have helped you recognize the situation? Like you subconsciously might pick up on the fact that hey the "dot" is on target but the front sight isn't where it ought to be? [Edit: I hadn't refreshed the page to see Archer's post or your response before hitting submit, so it seems the answer may be no.]
I'm just getting into red dots on pistols so I have not yet experienced this in real life...and the sun is nowhere to be seen here today...so I grabbed a flashlight to experiment. I was easily able to create a false dot with a small flashlight on low at close range. When the light is very close to the sight, I found it interesting that you can see the details of the emitter and orange peel reflector in the red refraction (if that's the proper term). As distance increases, the image rapidly shrinks to a point that looks like a false dot. Below is a quick pic through an SRO. With a brighter flashlight, the effect was easily created across the room. The other sight I had near is a Vortex Venom, and while it also projects a false image of the light, its false image is much dimmer, not tinted red, and could never be confused with the dot. When looking at the two sights from the front and observing the reflection of something like a ceiling light, the SRO reflects that light with a deep ruby red tint, whereas the Venom reflects it as a pale pumpkin orange. Surely Trijicon was aware of the different coatings and their effects, making me think it must be about tradeoffs somewhere, but what benefit of a coating could be worth the severity of the false dot?
Another thing I noticed with the flashlight test is when moving the sight (as in getting a sight picture), the false dot moved in the opposite direction of the real dot and much less rapidly. Have others noticed this in an actual low sun angle situation? If so, perhaps another clue the brain could use to recognize a false dot.
Close range flashlight and SRO:
Attachment 63650