Who inspired who?
This is only my guess, because I don't have any documented evidence to demonstrate my point of view, BUT:
The Milspec is a variation of an earlier FF:
The FF was released since 1953. The Bulova proto, AFAIK, was released at the end of the Fifties, so, later. The Military Specifications inpsired the design of both of these watches, BUT, when the FF has to adapt itself to the Milspecs, the Bulova had to start from nothing. So, to me, if the Bulova Proto and the TR 900 are so aesthetically close, this is because of the Military Specifications, and certainly not because the Bulova inspired the TR 900. The mother of the TR 900 is certainly this early FF, and the Milpsec one is just a TR 900 big sister, to me. As for the Military Milspec you show with the Compass, I think I know this watch in the flesh. This is another great watch, with a part of Mystery. To me, I think it is a TR 900 proto, as it shares the same case than the TR 900. It is a kind of cousin of the one I recently bought, an " AM " watch. But I will come back to this watch later... Best, Hermano, and thanks for your detailed answer! Nicolas