PvP Offense doesn't increase your damage, but it does cancel out a percentage of the the target's PvP Defense PvP Defense does increase your mitigation, but the amount it increases your mitigation by drops off sharply as the attacker's PvP Offense increases, which negates a percentage of all additional PvP Def you add.
This creates a lot of situations where additional points in each stat may do almost nothing depending on the stats of the target you're attacking, or being attacked by. The other problem with PvP gear is that the PvP stats on each piece are so high, that you run into very hard diminishing returns before you even have a full set equipped. The first piece of PvP gear can add over 20% Off/Def, the second piece adds less than half of that, by the time you're finishing off your set the diminishing returns are such that you're getting around 1% per piece. There are several logical problems with the system, like this:
If you're a full healer, your PvP gear is only potent against players with low amounts of PvP Offense. Having PvP gear against an ungeared attacker gives you huge damage mitigation, but against a player with a full PvP set the bulk of any additional PvP Def % you add will be negated, and the amount of PvP Def % you can get from gear plummets off to nothing on a sharp curve after a few pieces. Since using PvP gear involves a significant loss of attributes, and PvP Def does little against a fully geared attacker, healers can almost completely ignore PvP gear, perhaps only taking 1 or 2 pieces
If you're a damage dealer, you need PvP gear in order to mitigate the PvP Defense of other players wearing PvP gear, but as you approach a full set of PvP pieces the hard diminishing returns eventually make PvE raiding gear a better choice. Ideal gear setups will run around with only a partial PvP set, or possibly none at all because:.
As high end PvE raiding gear can come with 6x Omni sockets, socketing PvP stats into raiding gear can potentially replace PvP gear entirely, as you need very few stats before heavy DR kicks in making them weaker than regular attributes.
The current system makes very little sense to people looking at the gear or at their character sheet, it's unintuitive and it frankly doesn't achieve what it's supposed to achieve. I suspect there were objections to having PvP gear significantly increase damage dealt to PvE geared players, because of a fear of instagib ganks, leading to this current system where PvP Off only negates the Def stat, but the impact of PvP stats doesn't have to be 20%-per-piece huge, it only has to be greater than the equivalent PvE bonuses.
There are different ways of addressing this, but the double dipping DR has to change if this is going to make sense. If PvP pieces added 3-5% real damage/effective health per piece without any DR, and we did something about the 6x socket situation, then I suspect the numbers would work out quite well vs PvE gear. But we need to avoid this whacky gear meta where Player A's stats make Player B's stats worthless, and push Player B into using different stats.
Hope this gets changed as I don't want to have to Raid to stay competitive, although I hear the Legendary Weapons are ridiculous.
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