I wonder if Dungeon Masters cater for that in the start? Its kind of a cheat if you think about it because it allows each party to know what's going on with the other even though the characters aren't supposed to.
That could work in a tabletop environment if you have the space but it could make the game lag while waiting on the other group to get their turns in. In a Play By Post environment not sure how that would work without revealing what's happening to the others.
But Gk, a split party, creates more work for the Gamemaster. It is acceptable, to have characters who are natural loners, or a character that is naturally mischievous, within the party. It even adds flavor to the mix.
It could prove difficult for the party leader, to keep the party on track, if most have a tendency to go their own ways.