Mind you

I didn't outright state one way or another in the chapter. :) For all we know, Hermes might be taking on his "role" as a god for a moment much like the nice guy you might share a pint with at the bar takes on the "role" of a Supreme Court Justice: the way they act would be about "what they are at that moment" (function), but neither is the "Supreme Court Justice" taking over the friendly drunk, nor is the friendly drunk taking over/changing into the Supreme Court Justice.