Some of these instructors forget that they are logging the flight as P1, so they should be looking out of the window. It's called CRM.. Cockpit Resource Management. The student is PF and should be left to fly the airplane. If the pilot wants to maintain x.thousand feet +- 50 ft. how is he going to do that without looking at the altimeter..?
The same goes for controlling the heading +-3 degrees..
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