Unless they've changed it, Master Shapeshifter is multiplicative with the 10% from Naturalist so it's effectively a 4.4% damage increase (The display still shows x114% since they don't show decimals in that window, this is easily verified)
iirc Master Shapeshifter is the highest boost to damage/threat over Imp Mangle as Maul is the #1 source of both. I ran a bunch of tests (keep in mind this was back in Naxx, but I would think better gear would only add to the advantage of Master Shapeshifter) and the conclusion I gathered was that: Improved Mangle + Master Shapeshifter > Master Shapeshifter only > Improved Mangle only.
Since you prefer having Infected Wounds, dropping Improved Mangle would be the 'next best thing'. Shredding Attacks is pretty lackluster for tanking, so dumping that is fine.
Last edited by tuffmuffin; 10-02-2009 at 11:54 AM.
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