"Spell penetration will increase your damage.".
I cried, just a little, inside. And outside. Great big tears rolled down my face.
Now, spell penetration is great for PvP. And to a certain extent, if you are being resisted a lot whilst leveling, a little spell penetration will help you out. From my research (via WowWiki mainly), it seems to me that there's a certain amount of resistance that a raid boss or PvE mob will have that spell penetration will not overcome. Then there's a certain amount of resistance that spell penetration would overcome if a boss had it. However, a vast majority of raid bosses and PvE mobs don't have a vast amount of resistances that you have to worry about overcoming.
Quote from WoWWiki: "For example, A level 70 player casts a fire spell at a level 73 raid boss with no innate resistance. The level difference is 3, so the raid boss has effectively 15 resistance to all schools against the level 70 caster. No matter how much spell penetration the caster has, his spell's resist check will always be done as if the target had 15 resistance."
That is something that simply cannot be overcome. No matter how much spell penetration you stack on your gear. It's perhaps a subtle clue on WoWWiki (and maybe WoWWiki is biased, but oh well) that none of their information on the various raid bosses include information about their resistances that need to be overcome. (I didn't look at ALL of the raid bosses on WoWWiki, but those I have seen do not mention resistances that need to be overcome or dealt with.) The subtle unspoken idea, at least to my eyes, is that this is because spell resistance on raid bosses is so little as to be negligible.
On the other hand, spell hit is something that we do need to worry about. As a warlock, you're given suppression so that you can up your spell hit by 10% if you want. Now, if you read and look and ponder and do some simple math (and reading, since it mentions the amount you need right there.) you'll see you only need to have a spell hit of 15% to cap yourself for PvE at level 70. There's a nifty little chart that I wish I knew how to link or duplicate that tells you what spell hit you need to have, given your abilities. For a warlock with 5/5 suppression, you need to have additional spell hit of 76. Anything over that and it's wasting a gem spot or a talent spot.
Now, I've run with a few really really good warlocks and what they always said to me was 'gem out your spell hit for now, so you can use those points in suppression somewhere else. Don't worry about it. In the higher instances, you'll get gear that has enough spell hit on it that you can slap in damage gems.' (this is, obviously, a paraphrase)
Right now, Kikidas is overhitting and I need to decide if I want to regem a few things or respec. Given how expensive respeccing is, I think I'm just going to regem at the moment, given that any change in gear may mean I lose a gem spot that gives me my 15% and I'd have to re-respec.
For anyone interested, at all, in raiding, read this stuff over. If you're putting spell penetration on your cloak because you're trying to 'up your spell damage' then.. I don't know, because I'm a nice warlock, but by my fuzzy little imp Ruptik, do some reading. If you're putting in spell hit that gives you a 20% chance to hit something, then you're wasting your money, gems, enchants.
Once again, there is my caveat: I am not the end all, be all, know all of game mechanics, nor even of warlocks. But I do know SOMETHING about it. And what I know about it tells me that if you're raiding and trying to boost your power for raiding and PvE, you're better off putting in spell hit and spell damage in some combination. A fair warning, spell critical strikes depend on your spell hit. It seems like that's relatively obvious, but magic users roll 'twice', so to speak. Once to hit. Once to spell crit. Apparently, melee crit is evaluated differently.
In which case, arguably you want to make sure your spell hit is high enough to not be missing all the time, then go ahead and put on some spell crit gems/gear/enchants. Read the end of the link I included. Eh, I know people, ya'll are lazy.
Quote: "When choosing between equipment with higher spell critical strike or higher +spell damage, there are some things to consider:
- Spell damage increases dps by a flat value, and as such the less of it you have, the more adding one spell damage will (relatively) increase the damage you deal – in other words, at 100 +damage adding 1 spell damage will have a larger relative effect than if you have 1000 +damage. Spell crit scales with overall dps, thus one rating has the same effect on your overall dps no matter your spell damage – that is, adding 1% spell crit will raise your dps by the same relative amount whether you have 100 or 1000 +damage. With increasingly high spell damage, spell crit's absolute value rises dramatically.
- Some classes have abilities or talents which proc off of spell critical strikes, as do some items.
- Spell crit can lead to more unpredictable damage. As such, it can be powerful, but unreliable.
- In a group, a string of spell crits can lead to pulling aggro off the tank (and possibly a dead caster).
- Many spells, particularly DoTs, cannot crit. Spells that have a direct damage component and a DoT component (e.g. Holy Fire) are able to crit on the direct damage component but not the DoT. "
This one is a little more wavery for me. I'm a warlock. I do many DoT's. I do not, however, do only DoTs. About 35% of my overall damage comes from Shadowbolt. This is why my spec is not UA, but I'm dark pact/ruin instead. Arguably, and I do admit this, on long enough fights, a UA warlock will most likely out DPS me with comparable enough gear. However, I tend to do a lot of 5-mans, at which point I usually do NOT dot up the target, since it dies before any of my dots are half-done. For me, I have a rather high spell crit chance than probably most warlocks outside of destruction/PvP warlocks.
I do not consider myself, as I said above, the most knowledgable source on things in the game. But I do a fair amount of reading. I know my class relatively well. And when I see someone who is not a warlock telling a warlock that spell penetration is the way to go... or telling any mana using DPS class that's going raiding instead of PvPing that they should stack spell penetration...