Quick quiz - what are the three most annoying/frustrating things that cause you to become angry or annoyed with a game?
While the actual results don't really matter, chances are that unavoidable deaths are probably fairly high up your list. Cheap deaths come in a variety of forms. It may be the overly powerful boss creature. In a platformer, it may be a creature placed with the sole purpose of knocking you into a pit or other similar hazard. It may be a sudden, unexpected test of reflexes with an overly harsh punishment for failure. In a pen and paper RPG with a sadistic GM, it would take any number of forms ("You failed to spot the trap. Your whole party is bathed in cyanide gas and dies.") Regardless of the form it takes, it's frustrating as hell to be placed into a position where you have very few options to avoid death - especially if it comes with a penalty.
This having been said, I was shocked to see Mythic adding even more of these situations to Camelot (see the bottom of the page, the section on Druid and Bard magics).
One of the chief complaints about the RvR game is the overwhelmingly powerful influence of crowd control spells - often, the side with the better use of these abilities will win the battle. CC comes in three forms; there's stun, which is very short lived but prevents your character from doing anything at all (excluding dying, of course). There's mesmerize, which prevents you from doing anything at all until you take damage - then you're free. On the other hand, mez can last more than a minute at higher levels. Finally, there's root and snare - one of the two prevents you from moving, and the other reduces movement speed so much that they ultimately have the same effect.
To make matters worse, not only are these spells available, some classes can cast them instantly, with no chance of being interrupted. While on somewhat lengthy timers, there's nothing worse than seeing someone instantly halt you, putting you at their mercy. Some versions of these spells are even area effect, so a mere handful of casters could immobilize an entire attacking force.
It's the PvP equivalent of a deus ex machina; only it's not a god in the machine, merely another player with a highly unbalancing ability. (In the interest of fair reporting, I should note that the character I played in Camelot was a Minstrel, who had an insta-cast stun spell. This was mitigated by the massive amount of magic power it used, and was only a single target spell. Moreover, it was the only real way to kill any target remotely near my level.)
So, with certain classes carrying around the spell equivalents of an ICBM, Mythic decided to act. They added MORE insta-cast CC spells.
Now I can understand the logic, from a detached, theoretical standpoint. Hibernia had no insta-cast, area affect CC spells - give them some to equal things out! Unlike the mutually assured destruction theory of the nuclear arms race, however, giving everyone a tactical nuke only discourages the use if there's some sort of negative effects on the attackers. Using AE insta-mez doesn't hurt a realm at all; it vastly increases their odds of winning a battle. Suddenly, there's a lot more insta-cast CC flying around the battlefield, which means more unavoidable deaths.
Is there a counter? Yes - one of the realm abilities removes any negative status effects instantly. This sounds great until you realize it's on a half hour timer, and you can be hit by two different CC spells in a matter of seconds. It's like getting a police bribe in GTA 3 with the FBI chasing you - it may help slightly, but you still have the police and SWAT teams around.
So why not leave them in? There's no penalty to RvR deaths. No permanent, tangible penalty, to be exact - the fact remains that you're now watching your corpse lie on the ground while waiting for a resurrection, or you're running back to the battlefield and waiting for a teleport. Either way, the effect's the same - the player isn't playing the game, they're not having fun, and they're probably getting more frustrated by the minute.
When a game's supposed to be fun but isn't, people will stop playing. This especially holds true if they're paying for it.
The solution, then, isn't to give everyone access to these abilities. It's to remove them entirely. I'm not saying that crowd control should be taken out of the game - it's an essential part of PvE combat, at least in its current incarnation. Just make them ineffective against other players, and come up with some new PvP specific spells. If done right, the players won't cry nerf (much), they'll thank you for stopping the cheesy deaths and giving the battles more depth.