It is true that Duke Patrick’s mods for Skyrim are suffering terribly from script lag. That is however due to the Creation Engine handling scripts with all the grace of a gorilla in a china store; Creation Engine is overall a pretty unoptimized mess and the Skyrim world doubly so. But the script lag is in no way smaller than the normal network latency lag, even at 60 fps, unless you spend an ungodly amount of time optimizing your settings for both graphics and memory available, and run no other mods. And even then the script lag is anywhere from unnoticable to up to half a second.
Precision melee combat in multiplayer is by no means an impossibility. The Mount & Blade-games are testament to that, and they had a worse engine to rely on than the CryEngine. As is The Specialist-mods for Half-life 1, which had a simpler, but still pretty good, close combat mechanic. Dark Souls, if not precision in the same sense with different directions and such, also has tight combat that works online. And say what you wish of Chivalry and it’s arcadish combat, but it works well, even if a bit clunky by design rather than lag.
I will not pretend that the effort of adding co-op to KC: D would be an walk in the park, but it being developed in CryEngine really gives it an immense advantage over Skyrim (which would have been the best game ever made till now and forever more with co-op IMHO ^^ (and a tighter fighting system, but that is OT)). Skyrim’s engine just can’t handle multiplayer in any reasonable way. CryEngine has a solid multiplayer component to start from, making co-op, if not easy, than at least feasible.
I will love the hell out of the game even without a co-op component, I think, but I never can shake that feeling when I play games such as M&B (single player campaign) or the Elder Scrolls that “This would have been the best time of my life if I could bring a friend or two”.
So, I guess I agree with you, even if I did a long rant in response to your post ^^