Some musicians (oftentimes the younger ones) tend to work what they practice at home into the gig. Developing technique is an essential part of becoming a musician, but that technique can often times get in the way of playing music.
When you play music, a bandmate or music director may point out places where you are dragging, rushing, playing too many notes, not being dynamic enough etc… and the ego can get defensive and fight these comments which are usually perceived as criticisms. Why not take these comments to heart, go over your performance material, and see if there is any truth to what they are saying.
I say practice what you play, don’t play what you practice.