The way I'd handle 4cp vs 5cp Rips is based on the remaining time of the current Rip. If I'm at 4cp and the current Rip is running out in ~3-4 seconds, I'd prefer to wait for 80+ energy, Rip/Mangle and start a new cycle. Sometimes though, you get lucky with crits/OoC/2t4 and are sitting on 5cp well before the current Rip runs out.

Keep uptime as high as possible without wasting energy/cp (though of course, critting a Shred at 4cp [wasted cp] is preferable to energy spillover).

On the topic of the 2/4 T4 set bonus and specifically, which pieces to wear.

Shoulders and Chest seems to be the most common choice. However, as a feral working in Illidan at the moment I am gemming and enchanting my gear with Tanking in mind primarily, and DPS second.

Now my question basically is, isn't it better for me then to use the Shoulders and the Helm of T4? If I did, it would mean I could use a Relentless Earthstorm Diamond and the 16 Hit/34 AP enchant on T4 headpiece, and use the Stamina and Defense Gems/Enchants on T6. Instinct tells me this is probably a better choice for DPS, but I haven't run it through a spreadsheet.

Any opinions? How much "better" is T6 headpiece for DPS in pure stats over T4? Good enough that it's better, even without DPS enchants/gems, and I should use T4 Chest and Shoulders and a tank oriented headpiece? Or should I use T6 chest and T4 head and shoulders and go for different gemmings?

For helm, you use Cursed Vision of Sargeras from Illidan. Even before 2.3 AP change, that helm blows everything away.

If you have T5 pieces, you should use those for tanking.

Argument of "wasting" combo point is a bit abstract, so let me attempt to break it down.

After the landing of the 4th combo point, the player has 2 choice

1.Rip, then shred
2.Shred, then rip.

Assuming the player has X% crit, then that player has X% chance to generate an extra combo point on the next ability if he rips first, then shred.

If the player shred first, he will have zero chance of landing an extra combo point.

This is assuming that Rip is not already ticking, and energy has reached more than 80 that the player must make a decision. However, the order of event here DOES matter.

I'm afraid using T5 for tanking is not an option for me. I only have 2 pieces of T5 (We sucked at Defender drops. Hard.) and as one of our 3 official tanks I have a priority on T6 drops. My guild would hunt me down and murder me in cold blood if I then used that T6 for DPS, and tanked in T5. And rightfully so, T6 does after all offer better tank stats.

Using T4 and T6 Headpiece and Shoulders for DPS and Tanking respectively seems to be a nice option for keeping the set bonus, at least until I get Cursed Vision of Sargeras. (Which will take a while, we haven't killed Illidan yet and then it has to drop and I have to bid against every single other melee )

Warriors can also pot and have weapon procs. I'd rather take this if i have to choose. But I think I'm biased since I'm more in a tanking role in my raid than dpsing.
It also has to do with your argument of having a shaman in the tank group though. And if i have one as a druid tank I would still prefer GoA for its more dodge and more threat.
But yes you are right they could definitly restrict windfury to cat form by design. Nevertheless we cannot complain after this buff we will get with 2.3

Without reading 47 pages of this, is the consensus that 2pc T4 is better than 4pc T6? I recently acquired my 4th piece of tier 6 and I can't tell if the extra rip damage is superior to the energy ticks.

Personally, I'm going to socket my T6 with 5 Agi/7 Sta in almost every slot except enough yellow gems to activate my RED and enchant everything for DPS. [Elixir of Ironskin] and/or a -crit trinket more than make up the difference, [Elixir of Major Agility] is the best for Tanking/DPS anyway.

But if you insist on enchanting T6 for Tanking Only, then it's fairly obvious to use Head/Shoulders of T4. A post many pages ago in this thread showed Helm/Shoulders being the weakest T6 in direct comparison to T4 and due to the Enchants they're also the 2 most drastic differences between Tank and DPS (I'd mention Legs for the enchant reason, but T4 Legs are so much worse than T6) The Difference on Chest/Gloves only comes down to 4 sockets vs Head/Shoulders being 3 sockets meta and enchants.

Regarding the 4cp / 5cp Cycle Issue. This are my results:

ImageShack - Hosting :: 4cp5cpxf9.jpg

Edit: Somehow, the img-tag won't work

If you are above the line, 4cp is better, below, 5cp is better. The blue line is for 4t6, the purple line is for 2t6 - without any t6 you'd be off the scale.

This is when you are mangling. If you have a manglebot and only do shred, the 4cp cycle is superior (unless you get under 12s per cycle).

It's true that with 4cp you get a higher Rip-Uptime - which is good since Rip has the best DPE of all our abilities. On the other hand, you do more Mangles in a 4cp Cycle - which i bad since Mangle has worse DPE than shred. So this all depends on which effect is the most prevalent. And since Rip scales good with ap and not at all with crit, the higher your crit, the more ap you need to compensate.

First of all, thanks for the answers, and apologies for the giant wall of text in my previous post Just wanted to make sure I didn't miss anything of relevance. Just one small follow-up question:

I'm assuming this is because of the fact that agility and AP will both scale, as well as the two sockets on it - am I correct? (Apologies if this is a daft question - just trying to wrap my brain around the math.) Also, quickly looking through the list of possible items in that slot, it seems to me that the only possible replacement / upgrade would be [Thunderheart Gauntlets]. Am I missing something obvious, or is this one more example of Blizzard's fantastic itemization skills?

Given that the gem design actually drops. Otherwise, we are stuck with either 5str/7stam (which actually did drop for us) or 15 stamina? I feel horrible about putting none blue gem and given up the socket bonuses

On the side note: I find myself tanking probably 80% of the time. With that said, perhaps it is better to have T6 used for tanking primarily. Unless you have another druid in raids who swaps tanking positions with you and lets you DPS!

I am still undecided on both though.