Interesting points all around. I think one could summarize the beneifts by saying, with a potentially negligible loss in quality you gain an apparently larger format. This is preferred over shooting in a different format/aspect, that is, using more film in the longrun. Not to mention, anamorphic leneses could be easily added to the already existing cameras & projectors that were abundant in the industry.
Hence my interest... I could slap an anamorphic lens on any camera & likewise on any enlarger. If the optics are high quality enough I don't think print quality would be a concern.