Mr. Satchmo
urielsatchmoortegaMR.Jinx
It's not the teaching pro's fault if your ball position got out of whack while he wasn't there. It sounds like the things he wants you to work on came easier once you fixed your ball position. Unless he told you to use that certain ball position, I'd give him the benefit of the doubt here.
Sorry if I came off like a jerk. I really don't know what your instructor told you, and I also don't know if your instructor is good or not. I just know that I've worked on things my instructor told me to work on before, and it didn't work out until he saw I was doing something wrong.
Th best thing to do is to write down everything the teaching pro taught at the lesson that way if problems are creeping up, one look at the notes will clear it up. . .it's clearly not the teaching pro's fault if someone forgets their teachings