Sorry if this might be a bit offtopic..but:

Assuming you are hitcapped with Zhar'doom, Greatstaff of the Devourer, is this on par with Tempest of Chaos + Chronicle of Dark Secrets? My guess would be it's slightly worse, however im very bad at maths so im here asking for help.

Running with 16.79% hit + 3% hit from totem, here is my teron parse for this week (no coe again :/ and only 32% crit rate argh)
Wow Web Stats

This parse shows 0 misses. Theorically I should get 1% miss but I don't. The only way we can conclude anything about how things work is to have a sample size ridiculously large - which both of our parses aren't. Don't take it the wrong way but this is the same as if I posted that, using my parse, it seems I can bypass 99% cap and make it 100%.

With this said, I do have to bring something controversial to the table. I have seen many evidence of this over the months, but never felt like it was worth posting about since making any conclusion from it is nigh impossible. However, here is my observation:

It seems that the closer you get to 0% miss, the more partial resists you get. And vice versa. I rarely - ever - get 0 miss and sub 4% partials, while I can name quite a number of cases where I had lower partials (2-3%) but 'high' (2-3%) miss rate.

I said 0% to 3% (check my post "0%-3%") is what you can expect with fairly high accuracy if the calculations didn't take numbers after comma into consideration. with 15% you should on avg see 2% with +-0.5% so 1.5 to 2.5% is very normal (it's not actually really bad or anything).

Manly: I totally agree, but it's ridiculous really that I manage to get those resist rates at 16.08% (166 rating + 3% from EP). I think I'm cursed almost since the chance of getting 5% miss rate with 99% chance to hit is rather small.
Either way what you say about partial resist is something I've noticed as well, and a lot of the time it will happen when you crit, which is sadly a huge dps loss. It's very much worth looking into as I remember that the common number I see for partial resist with 0% miss is around 4-7%, often dead 5%.
RoS stage 3 seems to create slightly more mitigation then other bosses, 4-10%, without CoE. This week we had CoE and I had normal mitigation again. Though the samples again are way to small really but the pattern probably points to either RoS stage 3 has 80-120 fire resistance or as you do more damage the mitigation has a slightly higher chance to kick in.

Every time I see a crit coming up as partially resisted I think fuck, that is a waste. I can clearly recall two of those I got when raiding earlier tonight. I probably also got a shitload of resists on normal hits, but I don't remember a single one.

I am no psychologist, but as I understand it the human long term memory only records some events it finds interesting or shocking. This is the reason you still remember exactly how that kid beat you up in 5th grade, but can't recall what you where doing the rest of that year. Or you still remember that one time a lock feared you in a bg and you stayed feared for the full duration and died to Dots ticking with nothing you could do, while you dont have a memory of the hunderds of times it broke early. For geeks like us having a partial resist on an otherwise huge crit is no doubt in the same category, causing you to selectively remember those events and forgetting the others, making it seem like it happens a lot.

I suspect that is also the case with partial resists and miss rates, but I could be wrong ofcourse.

I have to see way more then that before I consider this anything else then a fluke. Keep in mind how RoS p3 works, if you get a 50% partial resist on your first hit you lose what? 1.5 k damage? If you get that same resist on a crit below 20% you lose what? 8 k damage? That is a huge difference. Not to mention it is a 40 second fight orso.

I was more thinking about looking at WWS parses then in-game notices regarding this, but I'm not going to refute how the long term memory works for some events.
According to wowwiki the formula for mitigation seems to be "Average Resistance = (Target's Resistance / (Caster's Level * 5)) * 0.75", which would yield us 3.21%. Now I am guessing the frequency of seeing 5-10% mitigation without CoE but with Arcane Subtlety and Spell Penetration on cloak would yield 15 to 63 with 48 resist removable through penetration or CoE.
15 gives 3.2% mitigation and 63 gives 13,5%.
In a fight where you were effected by 7% mitigation your target had 33 resist to your school effectively. Counting in 30 reduction and without CoE, your target had 48 extra resistance outside the base of 15 (which we can't do anything about). Add to the fact that it is possible for a mage to get another 18 and reduce it all the way to 15 again due to T6 shoulders. It might not be so far off to expect some bosses to have 63 resistance vs fire.
Anyway hypothetical and needs lots of research, but I can't help to wonder as of why they put exactly 18 spell penetration on those PvE shoulders.

RoS stage 3 is often flaged for the wrong duration in WWS, it should be flaged for stage 3 (Essence of Anger) when everyone gets affected by Aura of Anger but it doesn't (non-dmg event). This week WWS decided that we were fighting Essence of Anger when the dot was ticking for 1500 shadow damage. Which means 40% of the fight is missing from WWS "Essence of Anger" boss section selection (you can still see it all in the log though). A correct duration of this fight is roughly 60-80seconds. HP should be 3M, this week we had 1.9M according to WWS.

I'm quite interested in a look into the spread of Partial resists. Earlier today I disseminated data from our Locks through a full SSC run and noticed that 2 out of 3 of them (non hitcapped, bless their TC-alergic idiocy "no need for hit past 150") had almost 65% of their partial resists as 25% damage, with 20% at half-damage and 15% at 75%... Anyone have any knowledge on the distribution of partials?

It's a given that the expected damage reduction from partials is supposed to match the expected damage reduction on binary spells due to resistance (with, of course, Blizzard's oddball exceptions). There should be a thread floating around here somewhere with various fits on the distribution of partial resists (e.g. the frequency of 25% resists as resistance increases, as well as for other damage reductions).

I had the same impression as you until I started messing with different gear combinations in Vontre's spreadsheet. I think the answer will vary depending on your other gear and would encourage you to download the spreadsheet and plug in your gear. What I found when plugging in my end game gear set is that Zhar'Doom was actually 20 more dps than Tempest of Chaos + Chronicle of Dark Secrets.

Check the table under partial resists here for resist numbers and their chance at respective levels. It's taken from blizzards own resist table that is posted on their main site but for vs lvl 50 and then converted to 60 70 and 73.
Resistance - WoWWiki - Your guide to the World of Warcraft
Dirty copy & paste
Reduction Resistance Needed Partial Resist Amount
Lv. 60 Lv. 70 Lv. 73 100% 75% 50% 25% 0%
75% 300 350 365 25% 55% 16% 3% 1%
60% 240 280 292 11% 34% 40% 14% 1%
45% 180 210 219 1% 18% 48% 26% 7%
30% 120 140 146 1% 6% 24% 49% 20%
15% 60 70 73 0% 2% 11% 33% 54%

I have a question that's been on my mind for a while: I'm currently frost specced with full frozen shadoweave, and although I'd like to respec to fire, I can't currently do so without losing a fair bit of DPS. So my question is, should I change my tailoring specialization? Or should I just wait until I get better gear? My guild is just starting ZA and the 25 man stuff, which should give an idea of what gear will be available to me.

I am at the same gear level.

I bit the bullet and respec'd tailoring and made both sets, FSW and Spellfire with spellstrike to supplement. I found it very valuable. For the raiding game Spellfire is so incredible it won't be replaced for a long long while. It is ugly though.

Once you respec you will need new shoulders and new boots as Spellfire and FSW are not perfect mirrors. I have the S1 shoulders and the boots from Maiden myself. Both are great choices. There is a nice long quest chain for some blue shoulders as well [Spaulders of the Torn-heart]. There are numerous boots that are obtainable at your gear level as well.

Don't forget about the 3 piece bonus, while not enormous it kept me holding onto the set instead of replacing pieces for stat upgrades. Honestly I wouldn't trade out spellfire gloves till t6 as long as I was hit capped. Blasting makes a good replacement for the belt eventually, but I wouldn't break the bonus till eh, Vestments of the Sea Witch + Belt of Blasting were both available to me. Even then you're losing out on some damage, but your gaining a lot of floating +hit which means you'll be able to drop hit from other areas in favor of more +dmg. (Assuming capped hit)

When your raid leader tells you to get 10k hp as a minimum, you will be changing out of most of your spellfire and spellstrike quickly. A lot of raid fights have a fair amount of colatoral damage. Having 6k unbuffed is really not a very good idea, dps notwithstanding. If you can surive through the whole fight with full spellfire/spellstrike and 6k hp unbuffed, sure, go for it by all means. But this will get increasingly harder as you raid deeper into 25 man dungeons.

The only fight where this is even remotely necessary (or smart, for that matter) is Archimonde. I raided all the way through BT with about 8k fully buffed. What fights are a problem for you in terms of survivability?

Anyways, yea I kept my Spellfire set until I had Belt of Blasting and won the Vashj Robe, and kept the gloves all the way up until everything was on farm, and Azgalor finally coughed up a Vanquisher token.

I cannot believe you did Naj'entus 8k buffed, and survived with any degree of consistency. I'll accept that this fight in particular is special in that regard, and that you could have swapped in gear specifically for that fight only.

You can add 1500 hp with the frost ward, and you survive quite easily.

Talaril is not facing Kael, Vashj or T6 content. He is just about to start Grul.

Your advice is way too early. In no way does someone about do to Grul need 10k unbuffed or even buffed. Trying to get 10k at the Kara/ZA level will gimp a mage's dps. I don't recommend it.

This is true, and I have been known to eat dirt on many, many occasions. I did Naj'entus with 8300HP give or take, and survived every time assuming I was actually healed before another spine volley =P. Council is rough at times, but again, Envenom is about the only thing that ever threatens your life. Gurtogg is all about your healers. The damage is very predictable and safe. Teron... not really an issue at all unless you get the Shadow debuff.

Really depends on how much confidence you have in your healers. I have a lot in mine, so I can get away with less HP.

"survived with any degree of consistency"

That's the point I was making. Sure, you can survive, with sub 8.5k hp using frost ward, if you've got a healer assigned to you so you don't get needle spined immediately after.

I do Naj with about 10-11k hp, and have been needle spined immediately after a frost explosion. I think it's incumbent on me to minimise the load on my healers when I can help it.

We have another mage who doesn't value survivability as much as I do. Sure, when he doesn't get insta-gibbed he does more DPS than me. However, over an extended period of time (like a weeks raiding, or possibly even a night) I do double or triple the damage - because I take responsibility for keeping myself alive.

(I'm not gimping to do this either, normally I'm the #1-3 mage, and in the top 6 of damage).

Only fight in whole of hyjal and bt i bothered with HP gear is Najentus and my first time on Illidari Council. Najentus i get like 9.5k or something fully buffed and smack on a frostward. Never had a problem with 8.5k buffed on Archimonde, Illidan or anywhere else. Sure I might die now and then =D=D=D

One thing to consider, at least on Najentus, is the more HP your raid has = the fast you can throw a spine. If you're sitting at 9k HP buffed, any thing that comes your way needs to be healed up before a Spine is thrown to break a Shield. If every mage/priest in your raid is working with that "get away with as little as I can" attitude, you're going to have a lot more time to heal up and let him Regen before you can throw, as opposed to if everyone had 10-11k, you could potentially throw immediately, thus increasing your DPS.

There's really no reason not to play it safe in all of TBC fights.

Again the value of HP is very fight specific... You've given great examples with Naj, however there are a lot of examples where you can live with much lower HP without any special effort, and other fights where HP beyond a certain level is nearly a complete waste. Giving healers a buffer for when the raid takes a lot of damage is one thing. Giving your healers time to slack is just a waste, though. It's up to you and the specific fight to decide when more HP is just allowing the healers to slack and when more HP actually helps you live by reducing the situations in which you would be impossible to heal.

Given a simpler example, the first raid fight in the game where you just have to have HP for learning it: aran. If you cannot survive his pyroblast, you're going to die (and if you're learning him you're not getting him down before the pyro most likely). However at that gear level gearing yourself to take a pyro+fireball will require so much HP gear that your dps will be simply horrible, while healers can simply heal whoever he's targetting after the pyro and land the heal before he casts the spell, not to mention people can interrupt - even if your group is low on interrupts at least the first should be interrupted. So yeah going with 12k HP (8k pyro + 4k fireball) will be very nice for survivability, but if everyone play anywhere near reasonably well you'll do great with 8.5k.