This lady improved her vision and wrote a diary of her experience! I am doing the same!

"Right... "Using our system you can wear these glasses
instead of those glasses!" Where do I send my money?"

Keep the money. Consider it one of life's free wonders! Just like
exercising is free(save for a nominal gym membership) natural vision
improvement is free(tiny fee if you buy any books, glasses, aids to
help you)


"or as if you have some kind of training or experience in the
subject? "


I experienced my vision improvement myself.


"What about all those friends of yours who have improved up to 5
diopters? I thought that was your goal."


Most improve about a couple diopters. I helped this guy improve from
20/50 to 20/25 and his goal is to get at least 20/20. He used to be
better than 20/20 before bad vision habits.