I feel sure that by now someone has had this puzzle solved. If so, I obviously must have missed it. Assuming that this is still an unsolved 'Fender' mystery, what then have been the best explantations for the capital letter "D" that we see on the necks of those very early guitars? Any theories out there? .......plausible or otherwise? Even in the 'bible' of these guitars "The Blackguard" written by Nacho Banos, does the author admit to not knowing what information this letter could possibly be conveying, and to who? A mystery indeed. Anyone out there with a notion of what is behind this 'secret' letter "D"?