One of the fun things about playing a plate class is that if you happen to be dpsing and the tank dies then very occasionally you can swing into action and save the day.
It happened on Friday in ICC against the Blood Princes. The MT is tanking the flame guy and the shock guy, but bites the dust. I grab a shield and tanking weapon, activate defensive stance, hit taunt, hit shield wall, after a few seconds taunt the second mob and that's me baby - tanking two raid bosses as fury!
There is the sound behind me of two healers having heart attacks, but I ignore their whining, tell them to man up, and we take the bosses from 30% to a kill! I then do a lot of /flex-ing in raid chat.