Yes, we should have a politique des auteurs thread to which many of these comments will likely be moved, but I have nowhere else to respond but here, at the moment.
ex-cowboy-You make some very good points, and it's true there's a danger of one-offs falling by the wayside if we overvalue the notion of an oeuvre as a cohesive whole. I will add, however, that the truly seminal one-offs, think L'Atalante or M, will wind up being spoken for either way and are in no danger of being neglected. It's the Walkabouts that may wind up getting axed, but I digress. As for Rohmer and Fassbinder, there are certainly films of theirs that do in fact stand on their own, regardless of the entire body of work, such as My Night at Maud's and In a Year with 13 Moons for instance, but yes, they do still fit this model of the archetypal "experimental innovator". The most spot on example I can think of of a filmmaker who's consistently better than average but doesn't have a stand alone you could point to as a masterpiece is Claude Chabrol, but he's not at the top of the canon. That's the thing. Renoir, Bunuel, and Godard are all filmmakers who have made a few bona fide masterpieces, but everything they made still has something to offer. The same could be said of John Ford. Just about anything they made is interesting. Someone like Louis Malle, Kieslowski, Roeg, or Wim Wenders doesn't exactly fit that model. But even so, I don't think it would be particularly controversial if someone were to suggest that Lang or Vigo was a better filmmaker than Fassbinder, regardless of whether or not I would personally corroborate that statement.
The Cahiers group, headed by Truffaut, was also attempting to construct a certain narrative of cinema as "art as truth", since cinema was the one medium more capable of mimesis than any other. Thus, the medium's mimetic capacities should be fully exploited, and anyone doing anything less than that was to be lamented. This narrative of cinema as mimesis was embraced by people like Andrew Sarris and maybe to a lesser extent Jonathan Rosenbaum, and it appears to be the dominant conception of cinema within contemporary cinephile circles. And yes, there are dangers of certain one-offs falling by their wayside, since they aren't easily assimilated within this narrative. Think of guys like Antonioni, Bergman, and Fellini, or a film like The Leopard, which just winds up seeming clunky when attempting to be assimilated within this understanding of the cinematic apparatus. So how do we reconcile the dilemma of clunky films like 8 1/2 and The Leopard, or The Conformist and Last Tango in Paris for that matter. Godard, Renoir, Bresson, Ozu, Rohmer, Rivette, Bunuel, Akerman, and Fassbinder even are all easily assimilated within the "cinema as mimesis" polemic. Do we do some soul searching and rhetorically query ourselves on why Bresson and Ozu are superior to Antonioni and Visconti or do we realize the mimesis polemic has its limits and isn't applicable to thorough understanding of cinema, since it leaves out films like L'Avventura and The Leopard. Or maybe what Antonioni's attempting in his alienation trilogy isn't suitable to cinema. Or conversely, perhaps the narrative of cinema is synergistic rather than linear. So where do we place Melville or Marker within this narrative?
Then again, this 'cinema as humanism' or 'cinema as mimesis' polemic of Truffaut's may just be very Gallic in its execution, since in French culture there's certainly a tendency to shy away from the sort of "flattering" unhinged artistic expression of 8 1/2 or Walkabout or Red Desert. And maybe that's why Cahiers didn't have much to say about Last Year at Marienbad. Iconoclasm is generally frowned upon in France. Then again, maybe that's why Godard, Sartre, and Simone still rankle the Parisian bourgeoisie as well as just about any De Gaulle lover to this day. I guess you could say Truffaut was iconoclastic in discouraging filmmakers from being iconoclastic. It does seem like he wanted them to just shut up and tell the 'truth' instead of "expressing themselves artistically".
Parisian bourgeois film tastes can be summed up as follows. They love Truffaut, Malle, Chabrol, Lelouche, and Sautet, the last of whom is a far better filmmaker than Malle, but that's a whole other discussion. They tend to get a bit snarky with respect to Bresson, Rohmer, Godard, and even Bunuel, and many probably haven't even heard of Rivette. Someone like Pialat tends to get taken for granted, but surprisingly, they all seem to love Chaplin and Hitchcock, even the ones who'd get snarky about Bresson or Godard.