I ran across this question, and it didn't really seem to sit with the rest of the questions. To me, this functions as a distraction from this site's real work of how we deal with the text itself.
OTOH, much of this site's scope so far seems to be in line with the litmus test "is this the sort of question I might find in a biblical commentary?" I would say questions of authorship typically do pass that test.
And, indeed, there are cases where a change in author yields a significant change in interpretation, which is certainly relevant to this site as well.
So, what do we want to do with questions of authorship, and does this bleed into higher criticism more generally?