https://www.youtube.com/results?search_query=endmyopia+resul...
I personally went from -3.0 diopters to almost 20/20 vision. So either I'm experiencing a fabulous placebo or the 'known mechanisms' aren't as comprehensive as we've been led to believe.
An arbitrary "correction" of two diopters is within the margin of error of the possibility of initial overcorrection, choroid changes, inherent small variability in eye tests, and tricking yourself into believing your vision is better than it is. -3 is trivially myopic, but if you do manage a 4 diopter change, verified by an ophthalmologist, not an optometrist, then you would be a medical miracle and worthy of multiple case studies. Get on it if that's the case!