I think Mike Knapp's definition would pretty much exclude bonehead mistakes by local projectionists...Well, first of all, the 2.0:1 think is usually done willfully rather than accidentally, so while indeed "boneheaded", I'm not sure it is technically a mistake.
The question then becomes why would it not also extend to boneheaded mistakes ...errrr... decisions by studio executives such as with "Shane" at 1.66:1 (which would be the OAR by the above definition)? Or lack of infrastructure to support a director's preferred ratio on a large scale commercial release such as with Kubrick? Ignoring a filmmakers intent/preference seems pretty silly.
I'll be happy with whatever aspect ratio the filmmakers would choose to show the film theatrically under controlled circumstances and consider that OAR even if it was not shown that way upon initial release.
In the last three years, I've seen these films theatrically, in several different theaters:
North by Northwest
All of these films were projected at 1.85:1, even though that aspect ratio is incorrect for all of them.
Sorry, Charlie, there is nothing wrong with showing these two titles at 1.85, because that's the way they were presented in the vast majority of U.S. theatres.
NxNW was a VistaVision title, and D. S. was made well after 1954, which is when 1.85 became the standard flat A.R. specified by the SMPTE.
As an interesting aside, if you ever see a VistaVision print from Paramount in a movie theater, you will see a symbol that occurs twice at the beginning of each reel. It looks a lot like a "T" and an "F" superimposed and has three horizontal bars.
Those three horizontal bars happen to be alignment marks for the following A.R.'s, 1.75:1, 1.85:1 and 2.0:1, and should be aligned with the top masking to properly frame the image for each of the A.R.'s.
Hey, two different guys independently invented calculus at about the same time. One is more famous than the other, thoughSame thing happened with the telephone and the theory of evolution by the mechanism of natural selection. The trick is to get your story out to the general public first. In this case I think Mike K. wins.