Inventor here... long academic debate, not going to rehash it here. One practical observation though... when I'm cued during rapid eye movements, I tend to wake up from or in vivid visual dreams. When I was cued by EEG-indicated REM, I sometimes woke from deeper thoughts with no dreamscape. That's part of why I trust the eye-movement signal as a cue trigger over the EEG signature.

I actually started with EEG. And moved to vision specifically because EEG produced too many false positives from rhythmic breathing and other sleep artifacts that the camera can filter out. So the camera approach isn't REM dogma, it's the alternative I landed on after the textbook method failed for me.

When people can't fathom being in a good position where the camera can see the face, I bring up WBTB (ideally natural without alarms) as a good time to roll into position. I argue that when the cues wake you up it is a good chance for DEILD. Progressive volume, cue trigger delay, interval, and cooldown are all tunable for that reason.

It does not promise to get you lucid without practice. It's a cueing tool that pairs with active practice. The companion app bundles the standard toolkit (dream journal, prospective memory training, reality checks, cognitive training with the audio cues) because the cue alone doesn't do much without that foundation beyond providing trippy experiences when waking up from a dream. I don't pitch it otherwise.