Revalidation
It is P/ut.
The whole purpose of the flight is training!
P1 or P1s is logged when the pilot is in control of the aircraft and acts, even when not, as if the commander. Such as a First Officer throughout their handling leg or a candidate on test.
Being a training flight, whereby the Pilot is under instruction, the pilot cannot be acting as if the commander and if the Instructor is doing the job correctly will not throughout be controlling the aeroplane. Demonstration, student practice and critique, et al.
The flight if it is to be worthwhile should not simply rest on an Instructor,sat passively, giving no input as if conductiong a test. The Instructor should be pro-active in challenging the Pilot technique/decision making and in so doing demonstrate and providing constructive arguement. The Pilot can of course take it or leave it as they see fit but it is still Pilot under Training.