That would actually be worse. If the setting actually becomes important.. if there is a permanent change to the game based on a decision made at the point of beginning a new game..
That is really not what I meant. There will be multiple ways to connect to play co-op, which could be implemented in a sub-menu, to keep all of the multiplayer stuff together (rather than starting a game, and then working out if and how you want to play co-op).
Honestly? I'm not understanding how you're not understanding my comments.
One is arguing why it is implemented the way it is, one a way it could be implemented.
and they'll consequently complain that it doesn't work.
It can't "not work". The game was designed for drop in / drop out multiplayer. If it works in single player with one person controlling both main characters, it will work in multiplayer with different people controlling them.
There may be extra work involved in quest design to account for players being able to split up and do different things. Enforcing single player only might cut down on much of the dialog and design work, if that is what you were getting at.
In that case, a 'designed for single player' warning should be sufficient.
