Some sources say it affects stagger duration. Other sources say it does nothing. Can anyone confirm whether it's bugged and what the perk actually does, if anything, in the vanilla game?
Here's my understanding:
Originally, people misread the Tower of Strength perk and took it to mean that they would get staggered 50% as frequently. When that didn't happen, they thought the perk was bugged and useless.
But the perk is actually intended to affect the duration of stagger. This is a difficult thing to measure, however, since different things can stagger you for different amounts: dragon landings, shield bashes from bandit chiefs, Fus Ro Dah from Draugr.
I haven't tested the perk myself to confirm; all I remember reading is that the perk affects the duration and does work. Unfortunately, I can't remember where I read that - some of it was on the UESP, some of it perhaps elsewhere, perhaps in the Tips and Tricks section of the Skyrim Blog. So, take this with a grain of salt.
Now, assuming the perk works, I guess it would be of limited utility. Being staggered doesn't prevent you from moving around, drinking potions, etc. So if the perk turns that full-second stagger into a half-second stagger... is that worth a perk? You might think so, if you're on your way to Reflect Blows.... but sadly, that perk *is* bugged. Or, not bugged per se, but implemented poorly. (Essentially, Reflect Blows reflects back only the damage that you actually *take* from a hit... and if you've got 100 Heavy Armor skill, Matching Set, some Juggernaut perks, then it's likely you're not reflecting that much damage at all.) Still, damage is damage, and if you're making a real armor specialist character, it might be worth it.