Personally I only have one prot spec, so I just swap glyphs when it's really necessary.
When I was Dual-specced I ran:
Threat: Devastate + 2 out of Cleave/Sunder/Blocking (swapped around a lot)
Mitigation: Shield Wall, Last Stand, Blocking/Devastate (dependant on threat requirement)
As a single spec I simply run with
Shield Wall (+talent ofc)
Reasoning being that Devastate is by far the biggest threat glyph, as well as good utility. Shield Wall provides me more survivability and Taunt is just because overall, there is little major benefit from other glyphs. In fact the only thing I'ld feel worthy in a raid environment is probably Glyph of Sunder for twins or anub
I run SW/LS/Blocking, but am thinking of going with devastate from here on out since block value is so meh these days for progression based encounters.
Semi-related: Devastate glyph still adds additional threat for the 2nd application of sunder correct?
Haven't used Glyph of Taint yet, as I don't really raid, so its not a big problem for me.
I use it for Anub add tanking (we often don't have a hunter for MD) and I can't afford it to miss, especially on P3 where healing aggro is so insane. Also very useful for Algalon, as that fight is fairly intense as well, and you can't really afford to slip up.
Always have on Glyph of Devastate, then I have 4 stacks of glyphs I swap around (blocking, taunt, last stand, shield wall) and I replace them a lot
taunt/shield for algalon, taunt/block for anub
don't use last stand glyph that much now, more when we didn't overgear the instances
Glyph of Devastate
Glyph of Shield Wall
And I alternated between the following depending on the fight:
Glyph of Taunt
Glyph of Last Stand
I often forget to switch back to the Last Stand Glyph though, and I rarely notice the difference. I really notice the lack of Glyph of Taunt on Gormok or normal Faction Champs though.
Back in May I ended up using Glyph of Taunt when we were working on I Choose You, Steelbreaker. Landing that taunt at just the right second was too important. I think I used it for Lose Your Illusion progression as well.
I played with it again when we were starting ToGC 25. I had the kind of luck with NRB P1 and P2 where the taunt would miss and the knee-jerk Mocking Blow would too.
As I run 10 mans, there's a lot of hit on my BiS gear so i've had no real need to reach for the glyph, coupled with the fact that i can use vig for taunt refreshes too.
I run with two protection specs at the moment, mostly because I don't have the gear to do any serious dps. (and well, I don't like melee dps all that much).
Either way. I use
Taunt - Devastate - Shieldwall in my survival spec
Devastate - blocking - cleave in my threatish specc.
I mostly miss a 2 minute last stand in my threat and survival spec. Somehow I keep regarding Shield wall as a real panic button while using enraged regeneration, trinkets and last stand quite a bit more liberally. Cleave is only really there because it's handy for anub'arak adds.
Oddly I also miss my revenge glyph sometimes. It's not needed very often, but the couple of times it could have been handy somehow really stick in my mind.
I wonder why I keep hanging on to the devastate glyph. I've ran heroic TotC without it once and wasn't really happy with my threat, perhaps it simply was a night spent in bad form - but it stuck.
I usually carry some glyphs in my bag so I can change things on the fly should I really require it.
I keep about different stacks of glyphs on me at all times and swap them as required for each fight.
I use taunt on any fight with tank swaps or where I'll be taunting more then once or twice.
In general I tend to keep devastate and shieldwall in, Swapping my third glyph between taunt, vig, last stand.
Personally I'm not a big fan of blocking. Think about Glyph of Blocking's defensive aspects this way...
Progression warrior tanks wearing ToGC gear are looking at approx. 1800 SBV and ~20% chance to block fully buffed. (assuming no tier hat or pants, feverish dedication and honorbound.)
The boss attacks every 2 seconds. Consider a 1m fight. That's one use of Shield Block and 30 attacks.
That's approximately 9 blocks, 5 automatically generated by shield block, (10s of shieldblock, 2s per boss swing) the remainder blocked naturally (20% of 30-5).
That's 5 blocks with double SBV, for ~3600 each, and 5 with normal blocks of 1800 sbv.
Account for critical block.(60% chance of double block)
3 (60% of 5) blocks for 7200, 5 (40% of 5 + 60% of 5) blocks for 3600 sbv, and 2 (40% of 4) for 1800 sbv.
3x 7200= 21600
+ 5x 3600 = 18000
+ 2x 1800 =3600
43200 damage blocked minute
Glyph of blocking would add, ~4320 damage absorbed per minute. I see greater returns by popping an indestructible pot. Forgive my bad napkin math if I'm wrong, it's just ment to be a quick estimation.
As to it's offensive merits, glyph of blocking adds more or less the same SBV as swapping feverish dedication to tier 9.5 pants.
I just don't find blocking useful, it's nice that it has both defensive and offensive properties (one of the few glyphs that does), but it just seems lackluster to me.
I assume you were talking about as a warrior, but as a druid we have such a ridiculous amount of hit naturally on our BiS gear that I'm spell hit capped anyway - glyph of taunt is therefore useless.
Never used it.
1st spec (threat): devastate, blocking, vigi
2nd spec (anub): blocking, cleave, vigi
Don't really understand point of having threat spec without glyph of vigi. It's 5% threat more and the person with vigi has 5% less.
Also surprised so many people use ls/sw glyphs, they're completly useless in toc (were ok for ulduar though).
Obviously you're right.
But let's see when you need cds in toc:
-beasts: 1cd on gormok, 1cd on enraged worm.
-jaraxxus: you have to be kidding
-twins: once, when there's a shield on opposite target (not really needed but helpful)
-anub: p3, which is shorter than 2 minutes so no benefit from glyphs tbh.
Not saying those glyphs are useless everywhere. In ICC I'm gonna probably take them myself, I've just found it surprising that people use them for ToC. I've never had a situation in which I needed sw/ls and they weren't up. But maybe that's just luck or good healers ;). Tbh threat is bigger issue for me, I can imagine it might be other way around for other tanks.
What levels of hit rating are you prot warriors using? In my "big nasty" set I have 22 hit (but super high EH and def stats), my heroics set I have 7% hit, and in my "EH with some hit" set about 5% hit. Even in my 5% mix set I will miss taunts...missed 3 on deathbringer saurfang.
I'm curious if I could get away with swapping out to the taunt glyph in my big nasty set and be confident in my taunts (mostly) always landing or for those few fights also stack some hit.
2nd, Beasts: it's nice to have cooldowns back up for icehowl too, I've frequently found myself completely out of cooldowns on this fight in heroic. The glyphs are amazing. I would argue that actually ulduar had less need for them.
3rd, Jaraxxus, I agree he hits like a little kitten, but you can find yourself between a rock and a hard place if things start to go bad, but why would you need threat glyphs on this fight. Imo err on the side of caution and get survivability glpyhs.
4th, FC: I agree you don't usually need cooldowns on this fight, but it is very nice if you get CC'd, and again, threat glyphs here? wut? they don't even have standard threat tables
5th, Twins: In our strategy tanks don't move, so having 2 min shield wall for the opposite color vortex is close to necessary.
6th, Anub add tanking glyphs = cleave, blocking, taunt.
I don't understand the negativity people have about blocking and the glyph of blocking.
I use shield block as a reactionary survival cooldown rather then something I press everytime it's up. With 2k sbv and shield block up, you would be blocking for 4k normal, 4.4k with glyph of blocking and I assume 8.8k on a critical block ,that is not trivial mitigation.