Wow, this is a very OLD thread, not even sure the original poster is even still here...lol...but for the benefit of others and since this thing as resurfaced, as an instructor, I can tell you there are bad instructors out there. The first thing you need to check before you even think about taking a lesson are his/her credentials, if he doesn't have any, walk away. Here in the U.S. PGA is king, not sure about other countries, but I am sure they also have established guidelines for qualified instructors. Just because they work at a golf course doesn't mean anything.

Now back to the OP question, if I have a student that starts exhibiting complete break downs in fundamentals, or can't seem to master them, Myself as well as most good instructor, will start slowing things down, and drop back to half swings and really start back working on fundamentals... grip, stance, ball position, alignment, balance. Hey, if you can't master things with a half swing, half speed, and make solid contact, what in the world makes you think you can do it at full speed swinging a club 100+ mph..lol..hell I have had people doing chip shots until they could make solid contact with a closing club face thru impact. Work your way up, this also has the added benefit of forcing work on the short game the majority of the time. I still do this from time to time and I have been playing for over 40 years. Just my advice, tell the instructor you want to work on fundamentals, don't ask him/her to fix a problem, until you know your fundamentals are correct, most of the time that will fix your problem, what ever it is...