How it works:
Open menu on trainer, you're by default on spec 1, switch to another spec and you will be logged off. Upon next login, your talents, spell bars, etc. will be saved as the other spec you choose. You may alternate between these, but each time requires a relog so the system can replace all your stuff.
Video demo (early, lacking rename feature)
https://www.youtube.com/watch?v=W_wzyVO ... e=youtu.be
^ ignore the garbage production quality -- I recorded it very simplistically.
Screenshot of rename feature:
