For pvp no For pve yes.
Trials would be a lot more fun with my bro
It's just not that style of game. It's loot based and having guests on (assuming you don't transfer profiles) would make that person useless in any endgame pve and be put at a huge disadvantage in pvp
It's a fantasy, at this point, but obviously it would be a welcome feature. I'd rather have a decent game first, though.
They announced in summer of 2014 split screen will not happen. Stop being dumb, kid.