I'm on my way to High Hrothgar and when I reach frost troll area it was really dead end for me cause I dead just with two hit. (Still level 5 though)
So I ran away and ran away and left Lydia behind, but I always threw fireballs to attracted it to me. And when I reached High Hrothgar's door, I let it attacked me and then open the door. When I inside High Hrothgar "poof" Frost Troll standing behind me. And the Greybeards came and fighting it. They do not used weapons nor magics. But they used shouts! It's really cool when Angeir make it paralyzed by his shout, then the others burned it with their shouts. And Angeir finished it with 'fus do rah' and the troll flew away.
It's really rare sight to see. They're not face-up weapons like companions, nor dweling magic users like college guys. But they're use shouts!
It's sight to see.

Sounds pretty epic, although I do hate that as dragonborn we can't fight with shouts only.

Hmm, never thought of trying this out. I'd like to see the Greybeards in action as well.

Awesome, these old men are not as harmless as they seem

It would be brilliant if there was a quest where you can truly follow the way of the voice, and learn to shout without cooldowns, but you have to give up the use of weaponry, and if you do use weaponry you become corrupted and have to go through the trials again (this way, people could return back to weapons if they didnt like the shouts combat, and return to shout combat if they preferred it to weapons)

Did they seem harmless ? When they shook the whole of Skyrim (possibly even Tamriel) when simply calling my name I instantly assumed they were badass.

I can't say that they look intimidating in person when you go to high hrothgar, more like a good'ol grandfather you can have tea and talk out with.

cool story bro? try hitting them yourself if you really wanna see how badass they are

You mean ice shout then get frozen and still you can survive them with the right build.

Um... I think you may misunderstand what the Way of the Voice actually is, lol.

http://www.youtube.com/watch?v=qYCMTjkk_XE

You mean this?

Edit: Ah nevermind, this person was level 4. Same concept though.

The Greybeards are just the badass equivalent of a grandfather a bit like their modern wives:-
http://www.youtube.com/watch?v=hzFbxWANX9c
http://www.youtube.com/watch?v=InK2o91_vYM

I was on my highest level character once and decided to save and see what they were made of. Arngeir was meditating on the tower in the back yard of the monestary and a came up behind him with 2 storm thralls, tried to Fus Ro Dah him off the clifff... nothing happened.. So I took a few swings, he got mad, froze me, killed my thralls, and then the others were up there and I got hit with 3 Fus Ro Dahs all at once and flew a few hundred thousand feet off the side of the mountain and died.