Standard disclaimer - I'm a CRI not an FI, so only see people who have already passed a skill test with somebody somewhere.
Yes, absolutely, I've seen this several times. A pilot who has some very fixed ideas about their flying - positioning in the circuit, use (or not) of checklists and procedures, and is not prepared to listen.
A key phrase I've learned to be worried by is "I'm not trying to be a professional pilot" when I try to pick them up on poor cockpit practices. It's a phrase which seems to point at a very poor mentality likely to develop very poor flying habits, then defend them to the death.
Is there a solution? Yes, in my opinion, but the student may not accept it. Politely but clearly explain that there are fundamental deficiencies with their flying, which will take some time to address, and creating a learning plan (which may look suspiciously like the PPL syllabus over again).
Either they'll understand and accept the need for the learning plan, and go the journey with you, or they'll refuse to accept it, in which case it's a very short relationship and they'll go off and annoy somebody else. I've had both.
HD - I still use PERT diagrams for project planning. Damned if I can see how you use them in ATC?
G