Interesting theory, thanks for posting, enjoyed reading I do think there's some confusion with some stuff, like reality checks having to do anything with MILD. The deal is even though reality checks are encouraged to pretty much every method/technique, they're a exercise on their own. They don't substitute questioning (but the good thing is that many people have started to link one of the other, which is great!), and they don't make relevant significance to techniques like MILD. The reason you see them so much is because they are a simple concept that works, and it's easy to combine with any technique/approach. But many people only use reality checks inside a dream.

Where do these random realizations come from? Well my theory is that the reality checks ARE working, but in a subliminal way.
Those realizations come from something called prospective memory. It's the most important expression mentioned by LaBerge when he introduces the technique (MILD), but the high majority of people completely ignores it. Between a person that made 50 visualizations a day, plus 50 mantras, and one person with great prospective memory, it would be the second one with the best chances of having a DILD through MILD. This is because the mantras and the visualizations are there to help you developing your prospective memory regarding your intention of becoming lucid. Subliminal messages on the other hand, let's just say that they are a lot less effective than you'd think. Extensive research shows that while they might affect something...they don't produce significant results in creation of habits or decision making, etc etc. I recall a video of subliminal messages for lucid dreaming, but never heard people reporting that the simple visualization of it gave them lucids. But prospective memory oh boy...I'd suspect is in fact involved in practically almost every Lucid dreaming technique, even things like WILD. His effectiveness is also shown in lucid dreaming studies, putting MILD with quite a score on a review of many lucid dreaming techniques (none of the techniques analysed were proven to give regular lucids, but since the study was a meta-analysis...)

And it breaks down the question of "Am I Dreaming?" and builds upon the affirmation of "I Am Dreaming." Telling yourself "I Am Dreaming." is way more straight forward right? The moment you realize your lucid dreaming, that's the statement that crosses your mind. If you had this statement crossing your mind constantly, the chances of becoming lucid would increase. That is my theory.
I agree with your theory, but wouldn't it be way more simple if you called things by their names and said "I question myself"? Just because simplicity makes things so much easier to "understand" (yes, at a deeper level). Again, it's your technique, but grasping the essence of it seems an improvement. Food for thought

The main thing I feel like someone could address is the fear, that constantly telling yourself through out the day "I Am Dreaming!" can really make a person actually believe that they are in fact dreaming (When in reality they are awake). Well this is why I said reality checks are a great method. Use reality checks to make sure your awake.
As someone who reached a period in which my average day would include a reality check + questioning every 5 minutes (that's a bit under 200 per day), I'd say numbers don't make much change (because at a certain level, something more "permanent" shows up. That is, you're not talking about repetitive actions, more like a fluid state of mind, which I like to call awareness.). The reason is it doesn't matter if you make 50 or 200 reality checks: if you're doing them as a mechanical action, they count as nothing. It's easy to perform the action and it's "quite fast" (read: for the average creation of habit time) to integrate naturally, but when you talk about conscious and reflective reality checks, with the solid questioning, then you shouldn't worry about believing that you are dreaming. I do like your use for reality checks in this paragraph

Again, this is just my personal view, not some attempt to bring you over to the dark side, but it's always enjoyable to read this kind of threads and contribute to the discussion, even if we disagree ^^