Thanks for prompting me on this. I've been over the details so many times today that I totally neglected them above.
I'm running full IIS and SQL Server. The application lives in inetpub/wwwroot/devkentico.local (my supervisor's naming convention :P).
Also, my application is definitely an application in IIS, not a web directory, so I think that part of the message is a red herring. My research has shown most ppl that aren't seeing the directory problem have some sort of directory mismatch related to the top-level web.config file and the solution's top level directory. But those are left over from 8.2 and things were fine.