Fair enough. I suppose at this point its more of a cerebral exercise than anything since there isnt really any situation to use MS/SB while buffd up with enough dex for FTP to make a dif since, in said situation, you should jsut use evis anyway.
Basically this. Shark bite's 100% tp mod is 2.0 fTP, and my weaponskill set has dex 250+ dex in abyssea. Shark bite must be stacked in order for it to be useful, so you're comparing a stacked SB with a stacked EV. The first hit of SB would look something like this
(43 + 14 + ((250 x 0.5) x0.85)) x 2.0 + 250 == 586 damage critical
let's just say your attack is capped at 3.0 and you have a 1.4 crit damage multiplier
586 x 3 x 1.4 == 2461
Now evisceration would look something like this
(43 + 14 + ((250 x 0.3) x0.85)) + 250 == 370 damage critical
with the same bonuses
370 x 3 x 1.4 == 1554 damage critical
But that's it for shark bite; it ends right there. While shark bite is about 900 damage ahead evisceration gets 4 more swings to work with and the offhand hit (or hits if multi proc) which cannot critical on shark bite CAN critical on evisceration. Since we're dealing with a capped attack scenario a non critical evisceration swing will do approximately 350 damage (43 + 14 + 63 == 120 base damage on non criticals) and any criticals get the 1.4 damage boost on top of the added 1.0 pDIF.
Assuming you have razed ruins the only time shark bite is better than evisceration is if you are literally landing only one or two swings when you weaponskill, but that shouldn't be the case even on evasive things like Flame Skimmer. The result would have been the same with a lower attack rating as well.
This is just an example with RR but even without RR the massive mods still cater to evisceration more than they do SB. SB is not a bad weaponskill, but it is outclassed by multi hit thanks to enormous buffs and stats. Mercy Stroke and Rudra's Storm are another story, and I would argue those are better than evisceration, especially with the new reports that relic weaponskills have been beefed up heavily for people who have the level 90 weapon (or is it just tied to the weapon period? Actually from what I read it sounded like Mandau + Mercy Stroke is 25% stronger and the only requirement is actually owning Mandau itself)