I am still hitting deep/REM sleep - that isn't changing. If I weren't, I'd feel terrible.
It has been about 6 months of doing this all night, every night. So far, I feel myself.
The key is to use old familiar programs. Things you can visualize even though you're just listening to them. It's that familiarity that allows your brain to have a sense of comfort, while not really being stimulated.
I've been overcome with sleepiness at my desk when watching video games on Twitch/YouTube with a calm narrator (no excitable screaming thanks). Something about it makes my mind wander and generating the visuals but not being in control of them seems to be an important step to falling asleep. Sounds similar to what you are doing and maybe I should try it.
It has been about 6 months of doing this all night, every night. So far, I feel myself.
The key is to use old familiar programs. Things you can visualize even though you're just listening to them. It's that familiarity that allows your brain to have a sense of comfort, while not really being stimulated.
In any case, the experiment continues...