Like how does the game test if you blocked an attack? Does it just take the TriShape of the shield/weapon and calculate like that? Or is there a special collision box or hard coded value? I want to mess around with shield collision but I'm really not sure how its done.

Typically they have a convex collision mesh attached on the shield nif. I can only presume that is used for that purpose but could not say for certain but would make sense.

In Oblivion (so I suspect it is the same here) there is NO collision detection for melee weapons.

"Blocking" (and attacking) is done by comparing distance and angles and waiting for the "peek time" of the animation of the actors... not by "collision".

@spookyfx, have you messed with the range parameter for melee weapons at all yet in Skyrim? I've tried lowering those on most weapons (there isn't a global mult for this that I've missed is there?) as well as the hit cone angle, but I haven't really noticed the difference in-game.

What do you mean by range parameter? The distance a bow shoots or the length of the melee weapons?

There is a game setting for all melee attacks: fCombatDistance

fCombatDistance * Actor's Scale * WeaponReach (where fCombatDistance is a gamesetting) = "reach of the attack"

I was referring to the length of melee weapons.

And wow, can't believe I missed CombatDistance. If I ever saw it I probably assumed it had to do with AI.

Thanks a bunch!

So there would be no way to make larger collisions so that if you're blocking an arrow from the front, it doesn't suddenly hit you in the foot/head because you can't physically block there: (since you cant control how you block) ?

If I knew it would be in my mod by now.

There is a MERP thread in Oblivion Mod forum mentioned the collision combat-based for Mounted Combat Mod. I'm not sure how they do it, but it maybe possible, thou I doubt it.