This happens all the time. We have calibration walkthroughs with academic coaches and different leaders of the district office. I have a hard time with this aspect of instructional leadership. I feel it is not a true picture of our teachers to base their performance on one 5 or 10 minute visit. Often times the team is very critical of the teachers. It is my opinion that is very important to build relationships with teachers and calibration is not a necessary tool for improving teacher practice or student outcomes. It often feels like a "gotcha" instead of "here to give you support".