A lot of people have researched this (http://gettingstronger.org/2010/07/improve-eyesight-and-thro...). I've personally experienced it, slowing reversing my myopia over the course of many years. It took me a decade to develop so it seems fair to me that it also takes a long time to reverse.
Nah, your original myopia was probably just overcorrected (it is easy, overcorrecting myopia in a subjective acuity test results in a smaller and so seemingly darker and sharper percepted image). Your result of ten years of training in probably just onset of presbyopia and a less skewed measurement. And the talk has got nothing to do with myopia reversal training.
Can corroborate. I managed to take my vision from -2.75 to -2.25 over the course of about 9 months of what I would consider to be considerable effort.
Notably, after about 9 months I stopped putting in as much effort though I continued using under-powered lenses. My vision today is -3 (about 5 years after I got it down to -2.25)