My own calculations with some of my recent parses has 2 points of Lethality being a little over a 1% damage increase, as compared to around .7% back in mid-Ulduar gear. It no doubt has to do with the ridiculous damage increase of the ToC daggers, and a higher crit rate from the next tier of gear (4pc T9 will make it even more valuable). On the other hand, the loss of 4pc T8 has my Rupture accounting for only 6% of my damage, even on encounters that favor its uptime. This makes the Blood Spatter talent come out to around a .9% damage increase. So in my case, it looks like BS is going to be the talent the ditch for players who need Fleet Footed.

The loss of BS while going 3/3 Master Poisoner is really making me consider phasing Rupture out of my rotation. With the 3.22 changes to MP and Envenom, intuition would point toward such a rotation, but I've yet to see solid modeling of it. I would imagine that 100% Envenom buff uptime isn't outside the realm of possibility, although I haven't had a chance to test how feasible it is in current content and gear. A couple parses should make things more clear.

With Aldriana updating and re-releasing his own Mutilate sheet, it's highly likely that won't continue this any further. My intentions were initially only for a personal sheet to allow selectable buffs on the mutilate sheet (considering I mostly run 10 mans) but turned into a stop gap when 3.2 came out, teaching me the hard way just how much detail is involved in these spreadsheets.

Perhaps my boss won't get grumpy anymore because I might actually do some real work...

I guess it depends on how you want to get the most out of your 2 specs for Herioc 25 man. I love playing Mutilate and use this spec on Beasts, Jaraxus, Anub and with the interupt on FoK removed probably Faction Champs as well. So lowering my dmg by 1% on 3 fights (altough CCing on Faction Champions half the fight) to gain 3% on 1 doesn't seem like a good idea to me. Especially with Northrend Beasts Heroic not being that hard.

My other spec is combat which I use on Twin Valkyrs and trying to optimise for this fight. Since Twins is alot more unforgiving then Northrend Beasts I think using my Dual Spec for this fight is worth more in the end.

Faction Champs are all Murderable except the tree and the warlock's pet. Beyond that, loving Mutilate on Jaraxxus and Anub'Arak doesn't make it better - both have burst phases where Blade Flurry will double your damage.

Even when I don't agree with your claim that Jaraxus is a combat fight, I think it is besides the point here. My main spec is Mutilate and thus will I want to optimise for playing that spec on most if not all bosses.
So maybe I wasn't clear on this before but what I mean is if your mainspec is mutilate it is not worth it in TotC to drop points out of lethality to take murder since the only fight where it shines is Northrend Beasts and maybe Faction Champions if you are not on CC duty (which you most likely will be until your healer is down).

Basicly what your saying is I only play mutilate on bosses that are murderable and thus will always take murder. Well it would be a bit weird if people go against that ofcourse.


Edit: Annoyed at this discussion and thinking your 1% number was probably exagurated I decided to plug it in the new sheet Aldriana released yesterday and for me it comes out at a 0,69% Dps loss to take the points out of lethality so I guess I have to agree with you that giving up 2 points in lethality to take up Fleetfooted is probably worth it.

I actually use a Mutilate out of the gate with a Tricks on the MT. We have a warrior and by the time I've used mutilate, I can pop HFB and then SnD Mut, (hopefully at 3 points so I mut again) rupture(5point if lucky) mut(depending on time/procced CPs) envenom Mut till envenoms then mut til refresh rupture. Remember, when timing your ruptures, if you have a 5 point rupture into the mob, it is possible to override the previous 5point during certain times so I always check after I have just had a rupture tick to see if it will override, if it doesn't override, it will tell you. Therefore, envenom and prep for another 4-5 point rupture. This is a judgment call for me based on timers and what not as well as the mob. Always worth it on Beasts to try and get a rupture in on Acidmaw/Dreadscale and use those CPs when they are underground otherwise you lose em. Others may not agree with me but this is how I have achieved my highest DPS through multiple in raid testing.

That thread can be found here in the Incoming Rogue Changes section in case you haven't found it already.
Incoming Rogue Changes Discussion

Try out the new mutilatesheet aldriana posted. Pretty soon after it is viable to switch to T9+offsetpieces 51/18/2 takes over in dps. Dropping rupture from your cycles frees up the talentpoints you need for fleetfooted removing the need to take these points out of lethality. It is a ridiculously easy to play cycle and it becomes more of a game of how do I chain the envenom buff the best.

Not having to think about rupture anymore also makes it less stressfull to keep your damage high on target switching fights. At least I got a really noticable dps increase on Jaraxus and Faction Champions.

Where is Aldriana's new mutilate sheet? This is the second reference to it I have seen but I can't seem to find it. The old sheet is still up on the Combate and Mutilate post and this post appears to still have Thaela's sheet.

mutilate_1.1_beta_2_.xls
The sheet is attached to the combat and mutilate thread.