Remember when you made 'crib notes' for test taking back in the day? No? Just me? Well, you didn't write the entire answers due to space limitations. All you really needed was a key word or phrase, or maybe a formula.
So they wouldn't be whispering whole answers over the wire. There's no way gramps could listen and talk at the same time. They would just key phrases or words to trigger the coaching that he already got previously to the suppled questions.
Or when he gets in trouble. They probably have a few 'escape' lines teed up.
