Looks like we replied at the same time Bart2.
I agree with most of what you say however
I can immagine using this when there is a problem with the cutout switches, re
is not how I picture it unfolding. If the cutout switches themselves were playing up you would diagnose an electric trim failure and just trim manually for a flap 15 landing and never touch the switch. If on the other hand you diagnosed " Jammed or restricted Flight Controls" you may well use the switch.