Re: Is it proper?
All teachers have their own style of communicating information. It may be the way he was taught. Focusing on details is important in my opinion because if student constantly do techniques with bad habits they are building memory in their nervous system and muscles making it difficult to change later.
What I hear you saying is that your instructor focuses too much on what you are doing incorrectly and not enough on what you are doing correctly. When changing styles or instructors with different ways of performing techniques, it can be challenging. Has anyone talked to him about the discontent with his negative feedback?