Now I suspect this is quite the controversial topic, but I also suspect I'm not the first to have thought about it. Simply put it's the idea of having two Game Masters running the same game, using clearly defined roles such as "handling the main story-line" and "NPC's and improvised events". Basicly one is GMing on a macro level, and the other at micro scale.
We're completely new to the thought and haven't even written a campaign yet. This would also improve our ability to split the group with a satisfying result, as well as keep-the-players-busy-while-researching-rules etc. Has anyone tried this before? Do you got tips or experiences? What works best/worst? What do you think?