You're probably right, and I think that's the biggest technical challenge inhibiting cross-faction PvE. With the justice system and it's PvP flags, they are obviously looking into how the flags work. Hopefully they'll be able to reverse-engineer the flags after that so thatstarkerealm wrote: »Which of OP's points? I also don't think open world PvP is necessarily a good idea, but I don't see any particular [non-technical] downsides in cross-faction PvE.
I have the weird suspicion that the different alliances inherit an automatic PvP flag when dealing with players from the other two factions.
I could be wrong, but its one of the only explanations for why Cold Harbour is faction specific, rather than turning you loose with players from all three Alliances.