I missed the hole on the front strap. Agreed it isn't supposed to be there (how on earth can you tell its threaded? Eagle eyes?). This pic is an unfinished "lunch box" gun, is it possible that this hole is used for a factory jig point that is later filled in? Is it possible that this particular gun (or just frame) was used in the factory for a different purpose other than a finished firearm, and that's how it was easily removed from the factory? (a display, machinists practicum test? who knows.)
Of course I can tell, it's my handgun