Yes, you are 100% correct, I have been told that many many times during my lifetime. The 'stuff' you are trying to identify is BS, that is what I'm made of
Just remember, I was only trying to help you and pointed out exactly where a top optician is that can 100% help you, and he is not expensive and in the grand scale of things, not too far away.
I hope you find the information you need on the net and a local optician you are happy with.
Rob