Libram of Obstruction?

Ok can some one please tell me when this Libram would be preffered over our Libram of Libram of Repentance?
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Because 107% is no better than 102.4%.

Whereas +fuckton block value is always useful.

You can get block-capped without it, basically.
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This isn't the "Offtankadin" forum.
Knaughty of the Nightfall.
Tanking 101 and Advanced tanking

There is basically no reason you would ever equip the Libram of Repentance over Obstruction.

It's worth 2.56% block chance at 80. Not even remotely worth the 450ish block value that Obstruction gives.
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And the emperor still wears no clothes...

Does it have the same urgency attached to it though, as the Libram of Repentance did in TBC?

Or more specifically - I'm currently a good way off the block cap. Would it be better to spend emblems on gear to reach that block cap before buying the new libram, which would obviously shine the more you are blocking?

god, does that mess of a sentence make sense? Should I focus on gear with real 'stats' to reach BC before buying the Libram.. or should I rush out and buy it with my first 15 emblems?

My armoury for reference:
http://www.wowarmory.com/character-sheet.xml?r=Dath%27Remar&n=Thoragk

At 2/3rds up time, the 458 BV (after scalars) is often a larger upgrade than other emblem items.
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I reserve the right to refuse service to those that do not read the stickies.

Really back of the envelope math:

Libram of Reprentance: 2.5% block chance increase.

Presume starter gear BV of 800.

Presume below block cap.

Therefore, 0.025 x 800 = 20 incoming damage less per incoming attack.


Libram of Obstruction: Increases block value by 352 with 5/9th uptime presuming 96969 rotation.

This presumes a normal distribution of blocked attacks relative to judgements, no reason this is not the case.

Presume Base Block percentage in starter gear of 12 percent plus 30 percent from holy shield.

Presume charges are not eaten through (the benefit would go down once they were eaten through but this would require a big aoe pull).

So 0.42 x 5 / 9 x 352 = 82 less damage per incoming attack on average.

Now also consider the fact that every so often you get to add 704 damage to your shield slap and that's on top of 400 percent greater damage reduction than the old libram and yeah, its awesome.

My math is always subject to ridicule and correction, though.
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