Hi Tory,

You’re right...I inadvertently tested the proposed solution with the
latex backend, but it turns out there’s a small difference between how
the latex and beamer backends calculate their \author.  I think both
backends should behave identically here and that the latex behavior is
more correct (i.e. #+options: author:nil suppresses generation of \author
entirely), and the attached patch makes beamer follow latex’s lead.

(It actually seems like there’s an opportunity to factor lots of common
code out of both backends’ template functions, making mismatches like
this less likely in the future.  But that’s a bigger project...)

Sorry for the confusion,
Aaron