i don't know if this is the same behavior but when i get staggered ( the animations wherein the screen sort of gets shaky) , i noticed that when in 3rd person mode the shakiness persists (all my enemies are dead but still the screen is shaking persistently) though in 1st person mode its already gone. I have to sprint in order for the shakiness to subside.(i try to play 3rd person coz i think 1st person mode is limiting my view). don't know if this a bug or intended but could you look at it.
also when changing the staggering config thru the scroll, it always says "player can..." so there is no way to confirm if you don't want it. it should show "player cannot..." if you don't want that action.
I'll take a look into third person.. I never play in third person myself so could be why I never noticed it

About the stagger configuration.. well the menu says that there is an option below (called ''Prevent stagger spam'') and that the option is enabled by default. Also, when you pick an option you'll get a popup explaining what mode the option is in now, so if you accidentally switched to the wrong mode you can always switch back
EDIT: just checked, I wasn't able to reproduce the third person problem... is it possible you have some mod which sometimes adds a constant ability to the player which has negative effects? If so, I think I'll include a condition not to stagger if the caster and the target of a spell are the same, that might fix this problem in that case..