That's what I'm afraid of.
Co-op mode allegedly shares a life bar and items, and you need to help each other solve puzzles.
From the sounds of it, however, it could be like the other players are in some parallel universe and you each fight your own monsters and never really interact. That, IMHO, equates a big bucket of
suck.
I was looking forward to the thrill of shooting zombies off each other's backs, like in RE0, and having glorious hold-out gunfights where you and your friends are backed against a wall while hordes of zombies try to make it through your hail of gunfire. From the sounds of it, this is not what we're going to get.
-SB