ableman Don’t see how qa will help on that except for informing future cinematography.
I can't speak to the rest as far as on-site during filming, but there are occasionally scenes from SLR (and literally every studio) that have issues with their initial release: sound not properly synced or playing in the wrong audio channel during parts of a scene, portions of the scene where the director is talking that should have been edited out, etc. Just simple things that would be easy to miss or overlook for editors who are just viewing the rough cut of the scene on a 2d monitor and trying to condense hours of footage down to 60-90 minutes.
Someone doing QA on the "finished" product would help to make sure that a scene doesn't get released, only to be immediately pulled so it can be re-edited. To your point, it won't help if there was a camera or position issue during the actual filming, but it will help with pretty much everything else.
