User blog comment:NobodysWarrior/Skyrim Co Op?/@comment-3217145-20130302085421

I agree that there are points where it would be awesome (like a bullcharging Warrior and sniping Archer pairup), it just wouldn't work very well. Aside from problems mentioned, I think the biggest obstacle would be the amount of data the systems have to communicate to each other.

There are a ton of physics objects in Skyrim. It can cause your own system to slow down sometimes. It would be even worse if the game had to send data on ALL of those objects to the other player's system. Even just tracking the movements of NPCs in a game like L4D is a huge task, but you'd be lagging like crazy if your systems tried to communicate the XYZ axis changes, momentum, rotation, and collisions of everything that moves.

This is in addition to syncing enemy movements and inventories across the entire render area, referencing what objects are there (since the game remembers where the player left things), tracking arrows and spells so that they don't lag and become useless, syncing HP and status effects on enemies, etc. Even worse if one player runs to Markarth and the other to Riften; how far does the game continue to track the other player? Or is there just an invisible wall?

I don't think it would be worth it. They'd have to hugely dumb down the game to get multiplayerness working, and if they did that, I wouldn't feel like I was playing Elder Scrolls.