10/25 Difficulty Split

When Blizzard announced in Wrath that they were going to have 10 and 25mans dropping the same iLVL of loot, there was a LOT of noise about it. In response Blizzard made a ridiculous number of posts trying to assure people of their intent to make the two raid sizes more of a preference to the guild, rather than any sort of strategic choice. In theory this means that they were intending to make both 10 and 25mans of equal difficulty in terms of the fight itself, and excluding the logistics of running a larger raid. Originally Blizzard intended to reward people for their logistical effort of having 2.5 times more people in a group by awarding more loot PER PERSON. There was again a lot of noise about this, and eventually Blizzard backed off of this idea, going back to making the raids identical in nature, with absolutely no difference between one and the other, besides the number of people you bring (of course anyone that knows much about probability understands that having more pieces in total drop means a higher chance of seeing those elusive 5% drop rate items, knew I would get called out on that if I didn't mention that now!). So how did Blizzard do as a whole on making the raids balanced?

Poorly. Now before I get too far into this, I want to say that there is going to be a lot of disagreement with what I have to say, but I am going to provide as many facts as possible to back up my opinion, and while many of them will be biased in my opinion's favour, that's not (entirely) intentional, it just so happens that this fun thing called Cognitive Dissonance causes people to ignore facts that are at odds with their beliefs, so feel free to direct me to dissenting opinions in the form of blog posts!

Looking at the majority of the ranking sites you find that they first do a horrible job of splitting 10 mans and 25mans because of how armory works, but if you can get past that (for example by using an awesome though not well known site like WoWTrack) you will find that 25mans have progressed much faster and on a larger scale than 10 mans, in fact only 3 guilds have cleared the first tier of cataclysm raiding and they've done it quite recently, as opposed to the 45 guilds that have done it on 25man. Now there are a few ways of looking at this:

1. 25man guilds are more prevalent and by simple statistics are more likely to have advanced further (False, 4,000 25mans VS 44,000 10mans)
2. More of the "hardcore/hi-calibre raiders" are in 25man guilds. This one is a very plausible suggestion, considering that most of the top guilds from Wrath are still in the 25man format (Ensidia, Vodka, Method, Paragon, etc.) However, the problem with saying this is that we really can't determine whether or not they are 25man guilds because they were in the past or if they are because 25mans are "easier" and therefore encourage guilds interested in doing world-firsts to take this format. An argument could be made in this direction considering that in the first week or two Ensidia actually tried to take advantage of the flexible raid lock by doing a fight on 10man, only to discover it couldn't be set back to 25man after, effectively costing them a week of progression raiding (given that they missed World third full clear by 6 days, that's quite a hit).
3. 10mans are, on the whole, harder.

My belief is that both two and three have a bit to do with this. If you are in a guild as skilled (and almost a little ridiculous) in their game play, why would you possible go down to a 10man guild? There are definitely disadvantages in terms of less class variability and therefore less "utility" abilities. Not to mention you don't want to say by to 15+ raiders and find out that next tier one of you raiders is burnt out and doesn't want to push as hard, suddenly you are down a very difficult to replace player.
However, the premise, which I have taken the long route to get to, is that I believe that 10mans are harder overall. A few examples to back this up that pop to mind?

1. Nefarian phase one has two dragons that must be kept 60 yards apart, meaning 2 tanks are necessary. Plus you have adds that must be kept away from the front of the dragons. On 25man you throw a third tank in and suddenly you have no issues with that phase. On 10man, you have to CC SIX adds, if you don't have the right mix of cc available (or a feral dps that can go bear and still be a fairly respectable tank) this fight is impossible, you would have dps and healers taking hits left and right, and very little dps on the dragons.
2. Heroic Halfus. This is a little less apt of an example, because it is still 2 tankable, however when Blizzard changed the mechanic that the Drakes had to be killed before Halfus received the damage debuff, they effectively took away the need to release only 1 - 2 drakes immediately, while removing the ability of disc priests to heal around 30,000 HP per Second, while keeping extremely full on mana. The easiest way to do it now is to throw a third tank into your 10man and have one tank just hold some drakes, with no mortal strike debuff the third tank doesn't take much damage. (Don't think this strategy is the best? well maybe not, but we used it last night and after adding the third tank, 2 shotted him). It's a LOT easier to add a third tank or even a fourth tank, into a 25man raid than it is in a 10man raid.
3. Chimaeron. The reason that this fight is a bit easier on 25 than on 10 is because in Phase 2 when healing becomes ineffective, on 25man losing 6 dps is equivalent to losing 2 dps in 10man (17dps vs 5 dps, not 25 people vs 10 people), that is a LOT more time the boss spends running from one end of the room to the other and back again, as dps arrange themselves properly according to the threat metre. Now granted Phase 2 really isn't where most groups find themselves wiping so this is a bit of a "who cares?" point, but it's still valid.

Constant rebalancing in the form of Blizzard reducing HP and Damage dealt on 10man and 10man heroic ONLY side of the fight means that blizzard feels the same way (or maybe they are just avoiding the "noise" again, but I am choosing to interpret it as agreement). Specifically I should draw your attention to the fact that Heroic Valiona and Theralion were actually SO imbalanced that they were considered harder than Heroic Nefarian on 10man until Blizzard hotfixed in some EXTREME balance changes cutting damage and HP but HUGE amounts (apparently they were very close to values found in heroic 25man).

There are certain mechanics that honestly will always make it difficult to balance the two sizes of raids, such as healer circles (the pretty little circles they put on the ground) which heal X number of people at a time. In 25man it's not too difficult to drop a Holy Word:Sanctuary on 6 people. In 10 man, unless your Tanks, Healers, and DPS (range AND melee) are all stacked on one place, it's pretty rare to find 6 people in that area. also the advantage of being able to supply EVERY raid buff in 25mans, while in 10mans, it's pretty hard to bring every buff and debuff, even though Blizzard has Homogenized many of them (including three classes now giving Heroism/Bloodlust/Timewarp/Hysteria).

I know I have left out the 25mans that are harder (Al'Akir and pretty much any other one where space is constrained and there is a "spread out" style mechanic), and I am not denying there are some, I'm just saying that overall I think it is harder currently to full clear content in 10man. Any thoughts? (Stir, Stir goes the pot...)