Sorry, but from my perspective D&D (great fella's, sterling service) are not at the top of the list of 'Things to do when your lost' I teach.....
I think we need to clear up something here.
What you're teaching, and explaining here, is "things to do when unsure of position"
What I'm advocating is "things to do when you're lost" (the title of he thread).
There is a difference - lost is when you've exhausted all the options that you were taught during your PPL (those that you can remember) and it's time to bite the bullet. I sincerely hope you and your fellow instructors ARE teaching this because having someone going round in circles, 6 miles out and blocking the ILS, trying to work out where they are and not accepting they are lost is REALLY annoying