I think we're all misunderstanding each other here. When your response to Rickair's "unable" was "radar contact lost" I was assuming it in the regards that the instructor in this case is basically leaving the student hung out to dry.

I'm not saying you shouldn't give them the worst case scenario eventually, my points are you have to build someone up to these experiences, because w/o a base knowledge and partial panel skills. There are always the prodigy students(which I definately enjoy) who you can push very hard and really see what they are capable, but this is always up to the discretion of the instructor(whom we're trying to help out in this situation)