In patch 3.3 Blizzard is implementing a 20% dodge reduction via a spell that will be present in Icecrown Citadel's raid called Chill of the Throne. As Daelo points out, if your tank had 30% dodge, he now has 10%. They are doing this in order to negate the spike damage that's become prevalent in raids lately.
So while dodge will be nerfed, the ceiling on damage given to a tank will likely decrease. This will in turn, at least theoretically, make healing more about strategy (applying HoTs and planning heals) and less reactive (twitch response to apply the biggest heal at exactly the right time).
This is interesting to note as it's a move towards the Cataclysm way of tanking, as has been explained by Ghostcrawler: less avoidance on tanks, less spike damage, and thus requiring smaller heals.
Daelo's and Ghostcrawler's full statements after the break.
This post is currently being edited.
Ghostcrawler has also chimed in:For Icecrown Citadel, we are implementing a spell that will affect every enemy creature in the raid. The spell, called Chill of the Throne, will allow creatures to ignore 20% of the dodge chance of their melee targets. So if a raid's main tank had 30% dodge normally, in Icecrown Citadel they will effectively have 10%.
Why are we doing this?
The high levels of tank avoidance players have obtained is making the incoming damage a tank DOES take more "spiky" than is healthy for raiding. Ideally, tanks would be receiving a relatively constant stream of damage over time. This allows healers to better plan their healing strategy, broaden their spell options, and simply give more time to react. Tanks could use their cooldowns more reactively. Instead, the current situation is that if we make a hard hitting melee boss and a tank doesn't avoid two successive swings then the tank could very well be dead in that 1-2 second window. The use of reactive defensive abilities instead becomes a methodically planned affair, healers have to spam their largest heals just in case the huge damage spike happens.
We've been trying to do a fair amount to mitigate the effect of high tank avoidance on the encounter side of things during this expansion with faster melee swings, additional melee strikes, dual wielding, narrowing the normal variance of melee swing damage, and various other tricks. There's a limit to what we can do, however. So to give us a bit of breathing room we've implemented Chill of the Throne. Going forward past Icecrown Citadel, we have plans to keep tank avoidance from growing so high again.
We'll have this on the PTR soon so players can see the effects inside Icecrown Raid.
Additional relevant statement from Ghostcrawler yesterday:Our original estimations for tank avoidance would have worked fine had we not decided to add extra tiers of gear to reward heroic boss kills halfway through the expansion.
The Cataclysm design will keep tank avoidance at more manageable levels. The loss of defense skill counts for a lot right there. We are also considering giving bosses expertise or other ways of baking in Icewell Radiance -- basically the concept that bosses scale with gear rather than just hitting harder and taking more hits.
What I would like to see in Cataclysm is higher health pools but also lower heals (and tank avoidance) overall. Hopefully everyone won't be on the verge of almost dying, yet the risk of overhealing will be more real such that you can't just madly spam all of the time if you want to make it to the end of the encounter.
Patch 3.3 is the last major patch of Wrath of the Lich King. With the new Icecrown Citadel 5-man dungeons and 10/25-man raid arriving soon, patch 3.3 will deal the final blow to the Arthas. WoW.com's Guide to Patch 3.3 will keep you updated with all the latest patch news.