This idea has occurred to me. However, I've never seen anything in the films that would actually support the notion, and the most straightforward, reasonable, and obvious explanation(s) for a lot of characters' behavior contradicts it, including such prior to Skyfall and whether it leans on the fourth wall or not (cf. "This never happened to the other fellow"). I find it an amusing idea to consider in jest, but personally I think it would be fun-sucking and tedious were it actually stated in one of the films that James Bond was just a code name that the various agents had shared.
Agreed. Besides, I'd be much more interested in finding out if Bernard Lee's M and Robert Brown's M are the same character, or if Robert Brown was playing a completely different character who became M after Lee's passing, or (and this is my favorite) he's still playing Admiral Hargreaves from
The Spy Who Loved Me and he's just been promoted to become the new M in
Octopussy. That said, while I'm interested in that little tidbit, I'm also just fine with it never being resolved, either.
The code name theory is silly. It fulfills a need to explain something that doesn't demand explanation.
This.
But it is the exact same car that was used in Goldfinger and Thunderball. It has the same registration plate - BMT 216A.
Meaning... what? That it's supposed to be some hand-me-down from the previous 007s who were all named James Bond?
That's actually not such an outrageous theory. One could rationalize that every agent who assumes the 007 "slot" also assumes the "James Bond" code name that goes with it and they are all actually different people in the same continuity. The idea has a certain appeal but it's certainly not self-evident and I doubt what the producers had in mind with
Casino Royale.
I don't have time to look it up at the moment, but I seem to recall an interview with Sam Mendes clarifying that the DB5 in
Skyfall was supposed to be, clearly, the car from
Goldfinger, but that it was just a gag that was too good to resist putting in, even if the events of
Goldfinger hadn't happened to Bond in this continuity, the same way Judi Dench's M in
Casino Royale is still M, but not necessarily the same M from the Brosnan films. It may be a little messy continuity-wise, but I'm just fine with that.