I don't know why you'd assume Rake then SR then Mangle. It was shown a while ago that you do more damage (albeit slightly considering we're talking 3 seconds out of a 5 minute fight) with Mangle-SR-Rake, 30% more initial damage on top of 30% more total damage on Rake was is going to be greater than 30% more damage on Mangle and 2 extra seconds of Rake (2/3 a tic) especially when you consider that Rake tics can now crit, making it significantly more dpe than mangle with SR. Admittedly my math was with the 40% AP version of SR, not the +30% damage, but Rake gained more from that change than Mangle did (more of Mangle's damage is based on AP than Rake's)

So assuming you have a decent enough threat window to pop cooldowns off the bat... an 'optimal' opening sequence would be the following?

1. Mangle
2. Savage Roar
3. Rake
4. Shred
5. Tiger's Fury
6. Berserk
7. Shred to 5cp
8. Rip
9. Shred to 5cp, refreshing mangle + rake as required
10. 5cp Savage Roar
11. Shred to 5cp, refreshing mangle + rake as required
12. Ferocious Bite as Berserk wears off

I really dislike using FB right after a SR.

Even with berserk up if you use a rotation like that.

You'll be putting up your rip about 1-2 gcds into Berserk.

So at the end of your berserk you'll end up with.

0 Energy.
0 Combo points.
~10 or so seconds left on RIP.

To get back to 5 combo point's, if you crit 2/3 of your next attacks.
Mangle (34)
Rake (35)
Shred (42)
Rip (30)

141 Energy. Leaving yourself with several seconds of lost rip time. If you get any OOC procs then your fine (keep in mind TF won't be up because you used it right prior to the berserk), but if you get a string of non-crits or some lost energy from miss/dodges.

Mangle (34)
Rake (35)
Shred (42)
Shred (42)
Rip (30)

183 Energy

This can leave you upwards of 8-10 seconds of lost rip time.

Because of this I'll even sometimes refresh my RIP early in berserk, you might lose out on 15 energy that could have gone towards a shred but you may be saving yourself several rip ticks.

That's exactly the way I start nearly every encounter. Exceptions are, of course, fights where you have to save your berserk, for example XT.

Interesting concept.

I would imagine at the point where you are rolling around in CP you would want to refresh SR at 5 points, is there an actual benefit to not putting SR up at 5 points during berserk?

Ferocious Bite before berserk is finished obviously alleviates the issue where you finish berserk with a low rip timer, 0 energy, 0 CP, but this brings along the problem of energy waste. It is very difficult to get to a point where FB does not actually waste any energy with its secondary effect.

I did some quick math, and you won't be able to FB with no energy loss until minimally 12 seconds in berserk. (Assuming no OOC procs). Any earlier and you give up maybe 20-30 worth of energy you could have used to shred instead.

If I'm still over 40 energy while berserking, I will continue to shred even if I'm at 5CP. It's just not worth dumping your remaining energy into a FB if you have gotten some good crits/CC strings. If you see that happening, and you are still sitting at 50-60 energy during the last bit of your Berserk, refresh your SR or Rip early and keep shredding so that you can finish the Berserk at or near 5 CP with good timers on both Rip and SR. 2 shreds > 1 FB, so don't waste energy dumping it into FB's secondary effect during a Berserk.

Yeah, this is just not true. High score boards are not a good way to measure class dps. Among other things, this is because top dps scores will suffer from selection bias towards parses with high crit streaks, which in turn favors classes which have more to gain from high crit streaks. A better measure which doesn't suffer from excess reliance on outlier parses is to measure median dps among 'good guilds', but no public database exists to take such measurement. In theory (e.g. no interrupts and perfect rotation), feral cats have the highest expected single target dps among all dps specs, and had it for a while (at least since primal gore was added). In practice, feral cats seem quite competitive with rogues and warlocks.

For the record, I agree with your conclusion about the relative value of feral instinct vs feral aggression. The marginal returns on feral aggression are so low, that the best case to be made for feral aggression is if you need to burst down relatively low hp targets where it's not worth it to rip them, but instead to shred to 5 and bite. But there doesn't seem to be enough such targets in Ulduar boss encounters. Instead you see a lot of AoE. Honestly, I would even drop feral aggression for PotP, because the tactical value of going bear with -12% damage done, even in full dps gear, is pretty useful on many fights (for instance on Yogg for meleeing crushers). My intuition is that interrupted rotations you get in practice push the value of FA down even further from its low theoretical value.

Casting Rip or SR during Berserk is not a waste like FB is (at high energy), as they do not consume extra energy when used. The only time they would be a waste would be if you are clipping your Rip or refreshing SR when it has a long duration left, and that doesn't occur during the opening sequence.

I try to shred down to low energy (I don't mind if I am at 5cp, I keep shredding until I am at about 20 energy) then I ferocious bite. If I had a few lucky omen procs, then FB can often be my last attack under Berserk, if not, I can sometimes regen enough energy for 1 or 2 more shreds during berserk, leaving ample combo point generation time for the next Rip, this allows you to Rip at nearly 100 energy, basically gaurenteeing a FB on your next "cycle" following Berserk.

For the record, during normal play, I use a 4cp SR, 5cp Rip rotation, fitting in FBs where possible, but I like to use a 5cp SR during Berserk, because I am always wasting cps from shredding off excess energy anyway.

Not 50-60 after berserk, more like in the last 6 seconds of it. Refreshing an SR/Rip instead of Shredding if you are abnormally high on energy (yes, this does happen) is worth the GCD only if it will prevent downtime on SR or Rip after the Berserk wears off. If you have 6 seconds left on berserk, are at 5CP, and have ~8 seconds left on both SR and Rip, rather then continuing to Shred OR FB'ing, you would refresh SR and work your way back up to 5CP and then refresh your Rip once it fell off. It's a matter of balancing your highest DPE abilities with your bleed/buff uptimes in order to maximize them.

If I've got 24 seconds on SR, 12 seconds on Rip, 6 seconds left of Berserk, at 5CP, and at 20 energy, then I'll bite and try to get 1 or 2 more shreds in before Berserk falls off.

None of these things are going to make or break a druids DPS on the meters... we're talking differences of 1-2%. For those interested in that 1-2% though, it's there.

EDIT: Side note... so far, my best streak is 5 clearcasted shreds in a row. Even THAT does happen. Sucks during a Berserk though because you just sit at energy cap and are effectively wasting the cooldown.

Thaeryn is mostly correct though, there's no way for what I posted to not have significant energy wasted on FB's energy drain, and requires your OOC procs and high crit to come at a very specific time during the berserk in order for it to work remotely well. I'm still of the opinion that FB's are better than extra shreds if you can manage low energy waste because of shreds causing CP waste (iirc 1cp = 1250 damage), but I'll revisit my own cycle sheet and see if I can improve it by adding Shreds. In the end, it comes down to gear, luck, and comfort with the use of FB during Berserk, I recommend it toward the end, especially on XT.

I am thinking, significantly, of saving Berserk for the 2nd Heart when not doing hard mode (obviously) because of excessive OOC procs during bloodlust.

My guild actually kills him fast enough that we have back to back heart phases. If you know you are only going to get one berserk in, and that you are not doing hardmode, your idea of saving it for the second heart seems plausible. If I were you, I'd try it out and see what effect it has on your dps overall is.