TBH with my recent experience, I would normally side with the "multiplayer harming the single player aspect".
But, the focus seems to be on multiplayer as cooperative. If I got this right, you can have a campaign structure that addresses both the single player and multiplayer cooperative. IMO, the multiplayer will drain massive resources from the single player once you introduce PvP, since the team will be working on more aspects that are separate from the sp experience, like balancing player character builds against each other (which literally takes forever).
