It's splitscreen, so there's no down time. Both players can do everything simultaneously, they are not bound to the same environment. I surely recommend it. It will most likely be the only way I play it.
In Original Sin games there was a hybrid of split and shared screen, so you could change it on the fly. I hope they add it in this game too.
Couch co-op is finally making a comeback? (www.latimes.com)