we just finished trying lich king (10) heroic when suddenly the second healer had to go.
just as we were looking for a new one, in order to quickly clear it nonheroic someone talked to the npc and we finished him with 1 healer.
nothing special, but i think it kinda shows how huge 20% already ... and 30% will be.
http://www.youtube.com/watch?v=s-JKSJGwfTE
http://forums.wow-europe.com/thread....17557741&sid=1