This is just a quick rant that always comes to mind whenever buffing the non-healing aspects of a class with heals is brought up. The argument generally goes like this:
1. Raids need healing.
2. Raids need around X Healing classes.
3. Because raids need around X healing classes, making non-healing specs desirable will throw off the raid balance.
The problem with this argument is with statement 2. Yes, it is true that current raids may require X healers. However, take a look at how X has evolved over time. In the MC/BWL days, bosses had no enrage timers, and so in order to make a fight easier, the common practice was to stack healing, to the point where most raids brought around 18-20 healers, making 45-50% of the raid healing. This let you simply outlast the fight. Then, in AQ40 and Naxx, blizzard introduced enrage timers, and suddenly, the old style raids were too heavy on healing to beat the timers. Most raids switched to around 13-15 healers, or 32.5-37.5% healing. If so-called "off-specs" were viable at that time, that would have allowed roughly a quarter of the healers in the raid to switch to one of those specs. Instead, what happened is that those healers were replaced with rogues and fury warriors, but if the modern day shadow priest and enhancement shaman had existed, you can bet that you would have seen 2-3 of each show up in a lot of raids.
Now, fast-forward to the present. Right now, the standard amount of healers to bring is ~3 in a 10 man, and ~8 in a 25 man, which works out to around 30% healing. Since most fights these days are limited by your DPS, it is possible run with even less healing (EJ was killing bosses in BT with like 5 healers before they broke down and started recruiting).
So basically, the trend since launch has been a decrease in the amount of healers needed for a raid to be functional.
Now, imagine for a second that in Wrath of the Lich King (or even in the upcoming sunwell 25-man), Blizzard continues this trend, and really goes wild with enrage timers. We're talking insanely tight. At the same time, bosses that require 3-4 tanks become the norm. Meanwhile, healing requirements continue to shrink. All of this results in a "normal" 25 man raid bringing only 4 healers. Suddenly, the extra resto shaman, resto druid, and the 2 extra holy paladins are no longer needed for healing. Meanwhile, raids need, oh, say, 3 more DPS and 1 more tank.
If blizzard were to buff ret, prot, elemental, and balance, these former healers could now fill those missing DPS/tank slots, with new specs that would open up new options for raid leaders. Everybody wins.
Now, the question remains whether blizzard will actually do something like this, but so far, this is the direction that things seem to be headed in.
