a lot of vital points made here...
but, without wanting to be pedantic.... :-) :-) :-) , I´d like to quote MarkVIII:
My point to all this ramble is that a good level of pedantry - attention to detail and KNOWLEDGEof the academic and minutae - is REQUIRED by a pilot. More pedaticism is required for a Captain, and a LOT more required for an Instructor/training captain/check captain/IP/SIP.
While I´m with you for the most time, there is time and space to " let the guys go" and more important, let them make their own mistakes to learn. If you´re always "pedantic" it will be hard to learn and keep his motivation up. I´m instructing PPL(very seldom) and ClassRatings (more often) - now I understand that the line is not the place for making mistakes, the initial incident of this thread was such a minor one (IMO), that I honestly do think, not mentioning it at all would have been a good idea.