instructor time always being master on to master off.
What garbage. maybe when the instructor is replaced by a robot.
What about preflight briefing?
What about post flight debriefing?
How about a new student being shown how to perform a preflight inspection?
Should the instructor pop out to the flight line and turn the master on before beginning any of those?
It never seemed to be an issue in the past, pretty much everywhere I flew you had a dual rate and a hire and fly rate for the aircraft. All on tach time. The reason for the Hobbs in twins is that most of them don't have hour counters in the tachometers.