[Daereg]

I'm really tempted tbh, I tried healing for the first time not so long ago, and when healing the tank in Naxxramas, I noticed for a while, I could get away with not healing him at all, since he would get a few dodges and parries in a row, all I would have to do is be ready to cast a flash of light/holy light when he eventually did get hit.
Its on fights like XT HardMode, Vezax25 and now Steelbreaker Hardmode25; that I sometimes get worried, the boss'll be near constantly hitting me for huge amounts, and the only thing keeping me up is my stamina(48,700HP raidbuffed) I wonder though, would it be wise to stack say...dodge/defense instead of stamina gems/enchants/trinkets.
I would lose 339 Stamina from gems, about 100 from enchants, and then from my 2 trinkets, 317.

My stats would change as so:

• Health: 37619 > 30000ish
• Dodge: 23.66% > 31% through gems/enchants(36.4% with ignis/vezax dodge trinkets)
• Parry: 21.75% > at least 1% from extra defense and hand-enchant. I'd use Blade Ward too I guess.
• Resilience: 23 > 0, no need for it when over 5.6% miss.

Can't do the math to calculate defense and everything exactly. And I'm sure theres even more I could do to increase avoidance even more that I've not thought of.
But I'd be tempted to splash out on the scarlet rubies to test this out for a week or two. I mainly tank for the big hard-hitting bosses as I have the best gear of our tanks at the moment, before I do, I'm wondering how avoidance tanks find it when their avoidance doesn't kick in and they get hit for a large amount, considering their HP pool would be somewhat lower...

[Magnuss]

Avoidance is nice. There is a great thread in the Theory and Mechanics Discussion that talks about how avoidance acts like armor. Just because it diminishes does not mean it isn't still worthwhile. The problem with gem'ing or gearing for avoidance isn't actually that avoidance is bad or not worth it, but that you have to make sure you will have enough health to survive under the worst case scenario. Some of these bosses, particularly the ones mentioned, are some of the heaviest hitters in the game currently. It is a huge relief off of the healer's shoulders whenever you can avoid a hit at a critical moment. The problem comes when you do not maintain enough health to survive a reasonable hit from the boss.

If you were to change all of your gear to avoidance based gems and all your enchants to avoidance based enchants you would be putting yourself in a position to quite literally get 1shot by several mobs in the game. The up side to this is that with even a little bit of RNG on your side you could potentially go a hell of alot longer with less healing than a Stamina stacked warrior. However there is also another issue that comes into play here. Lets say that you did have a full avoidance set and it allowed you to rely on less healers overall for healing you (because obviously you would be avoiding more, so you wouldnt need the same level of spam healing). What happens when those healers get used to an expected trend to your damage intake and then you suddenly get unlucky. It would be very easy to catch a healer offguard and not have the health overhead to give them time to respond. If you are not using less healers, or your healers are not healing differently, then why bother with avoidance at all? What would be the true purpose of aiming for an avoidance based spec? Maybe you take less damage in a fight on a certain boss than you did before. Maybe you get gibbed too fast for your healers to respond.

Gear and items are available in the game right now that allow for you to create a high stamina gearset that will allow you to survive worst case scenarios when you have the right number of healers on you. It also gives a more steady feel of how you can be healed and how you take damage than the RNG based avoidance system.

Even with all that said, I believe Ciderhelm tried out having all dodge gems in his gear for tanking Vezax. It is a relatively recent thread and I believe he mentioned that he did not like it much, though I am not sure exactly what his thoughts are. Perhaps he can lend a better personal view on the matter. I personally, just do not see the reason to change to avoidance.

EDIT: here is the thread I mentioned Ciderhelm Dodge Gems

[Daereg]

Source: Magnuss Avoidance is nice. There is a great thread in the Theory and Mechanics Discussion that talks about how avoidance acts like armor. Just because it diminishes does not mean it isn't still worthwhile. The problem with gem'ing or gearing for avoidance isn't actually that avoidance is bad or not worth it, but that you have to make sure you will have enough health to survive under the worst case scenario. Some of these bosses, particularly the ones mentioned, are some of the heaviest hitters in the game currently. It is a huge relief off of the healer's shoulders whenever you can avoid a hit at a critical moment. The problem comes when you do not maintain enough health to survive a reasonable hit from the boss.

Well I think I'll maintain just enough stamina, with all the Ulduar gear, could probably have over 40k buffed, which could be enough to take a hit from Vezax and have plenty of time to be healed. But, is it all worth it?
Raidbuffed, I'll have 38-40% dodge and then the 23% parry on top, with miss and boss-miss. Its at 70%.
70% real avoidance(dodge/parry/miss) against a boss who isn't gonna be doing any non-melee damage against me. With Stamina I'm avoiding just half of everything, getting hit twice in a row a lot too. Tempting to say the least, considering 41K HP could very well be all I need for most melee bosses.

[Kerg]

Looking at the numbers you posted, I think a decent estimate of what you're looking at is this...

Before
48K hp
55% Avoidance

After
40K hp
65% Avoidance

By adding that 10% Avoidance, you will be reducing overall incoming damage by 10/45 = roughly 22.2%. You will reduce the chance of getting hit twice in a row from roughly 20.3% to 12.3%. And reducing the chance of getting hit 3 times in a row from 9.1% to 4.3%.

Problem is, as posted above, will you have enough hp to survive the worst case scenario? Say the boss is hitting you for 20K+. If you get hit 2 times in a row, which WILL happen 12.3% of the time, which means many times in a boss fight, if you're healing is slow for whatever reason, you'll die. If you get hit 3 times in a row for 13.3K+ each, which WILL happen 4.3% of the time, probably several times in a boss fight, if your healing is slow for whatever reason, you'll die.

So I think it would work fine most of the time. If your healers are quick reacting, you'll be fine, even when your avoidance doesn't work and you get the strings anyway.

But from time to time (maybe 1 in 10 boss fights as a wild guess), the stars are going to align, 2-3 big hits in a row are going to land anyway, and healing is going to be late for whatever reason, and you're not going to have the hp to survive it, and "squish". The raid is going to wipe, and everyone's going to be like wtf? And you'll *grin* sheepishly as everyone runs back from the graveyard and say, sorry, had an unlucky streak of hits there, and my healers weren't quick on the ball, and I died. Better luck next time?

Then again, every now and then, maybe one of your healers dies down the stretch... maybe all your healers are running out of shadow crash on Vezax at once, and all healing stops for 3-4 seconds. But you hit an avoidance streak that you otherwise wouldn't have hit with your lower avoidance previously.... you live through it and down the boss. Your avoidance saved the day. /cheer So you could get lucky in a good way every now and then, too.

You also have to consider that if you are a warrior tank, 22% less incoming damage means 22% less rage from incoming damage. It is going to have a severe impact on your threat output. And an "unlucky" avoidance streak at the start of the fight could wipe the raid if the boss is untauntable (like Vezax). This won't be an issue come 3.2, because you can get 5/5 Shield Specialization. But it will be now.

[Daereg]

No I'm pretty sure its closer to 70% than 65%, but anyways. With 3.2 changing gem values anyways, now isn't the best of times to go about filling my gear with subtle scarlet rubies. Besides that, reading threads like
Pally Tank: When are your stats too much?
make me realize how foolish I was to almost think raw Stamina wasn't the way to go.