Agreed, Warped Factor.
It was already acknowledged among instructors, particularly those operating close to the London TMA, that the use of 121.5 for training fixes was invaluable.
Just preventing minor nav. discrepancies becoming major emergencies or infringments by ensuring that students should have no fear of contacting D&D is small cost.
The fact that an early solo student still has help available and is not afraid to use it should things go awry can only be a major contribution to Flight Safety.
As a previous airline pilot with some "time" in, it has always amused me that the selection of Guard on Box #2 was not really of any real use except maybe over expanses of sea.
Perhaps the occasional reception of someone else's EMC ( or even an accidently-tripped EPIRB on a shore-bound dinghy) helped to relieve the boredom for a short while ?
As for accidently transmitting on COMM 2, by said devotees because of finger trouble, tune into the next ATIS instead, eh.