btw, another aspect I didn't see mentioned yet was flying on a buddy box. I don't know what your setup is, but setting expo on the master TX doesn't give expo on a regular buddy box. Same with dual rates.

Now, if the instructor holds a basic 4-channel radio, and the student is holding a computer radio, then you can dial down the students control rates with end point, d/r or expo, and the instructor can maintain a higher control rate to help with "saves". If both student and instructor have computer radios, then setup is even easier. But most times the student winds up with what amounts to a basic 4-channel box with 100% throw and nothing on any channel.

(more than once I've had to "unprogram" a new student's computer radio because he'd done all the centering and control throw settings in the computer radio. The buddy box does not have those settings, so it can actually be impossible to trim the plane out if subtrim was over-used).