Not too long ago, Blizzard buffed Focusing Shot, giving it a 2.5 second cast time, instead of the previous 3 seconds. This pulled focusing shot slightly ahead of lone wolf in DPS, at least in patchwerk style simulations. There are still a lot of questions about when it will be viable due to the restrictions to movement, but in general, if you want to pump out the most dps, it's time to start learning how to use this talent to its fullest extent.
One reason this is so impactful for MM, is that Focusing Shot now hast the same cast time as Aimed Shots, which means, for better or for worse, we've got to take another look at Haste plateaus or breakpoints. If you'll remember a couple weeks back, I did a little write up about the possibilities of Haste plateaus in the MM rotation, but came to the conclusion that with so many varying cast times and therefor so many varying shot combination times, there weren't any plateaus that were going to significantly change how we play. With Focusing Shot, however, at least half or the time, you'll have a more manageable rotational Haste breakpoint (for lack of a better term).
Again, just so no one misunderstands or gets upset with me, when I'm talking about Haste plateaus and Haste breakpoints, I am not referring to the value of the stat; instead, I'm referring to how we change our rotation, based on the amount of haste we have.
The Marksmanship RotationFor MM hunters with Focusing Shot, all throughout the first raid tier, at least, our base rotation will look like this:
The primary variation will be where in the rotation the Focusing Shot comes; we won't, however, have to think too much about that, since it won't affect the number of shots between Chimaera Shots.
There will also be times when we're casting either Glaive Toss or Barrage, and times when Ancient Hysteria or Rapid Fire are up, which will change our rotation; I'll cover those situations below. For now, we'll just look at this rotation, since it will be what we use most of the time.
The Effects of Haste
It's probably worth noting, that theoretically, at a low enough haste point (zero, for example), you may be better off only casting three abilities between chim shots, but since we'll always be raiding with a haste buff, at least, we can safely ignore that situation.
With that said, the first thing you might notice, is that until we reach 25% haste (if you're not familiar with how haste works, or don't want to do the math in your head, at 25% haste a 2.5 second base cast time ability only takes 2 seconds), we're going to have to delay Chim Shot. While ideally we wouldn't want to delay our signature shot, right now other stats are so much more valuable than haste that it won't be worthwhile to try to hit this 25% haste mark, and instead we'll just deal with having Chim Shot delayed a bit (since the only alternative is to have a second or more where we're doing absolutely nothing).
Even in mythic tier 17 gear, we're not going to be seeing very much haste. This is partially due to being the first tier of the expansion, but mostly because Blizzard has watered down the stats by adding two new, so we'll have roughly 60% as much of each stat, compared to MoP. Still, it's worth noting that at 34.2% haste (after raid buffs), it will be worthwhile to add in an extra Aimed Shot or Focusing Shot, giving you five total abilities between Chimaera Shots. If you're curious for the reason why, it's all spelled out in my previous post, here.
Other Useful Rotational Changes
With Rapid Fire as our primary CD, it seems looking at what the numbers will look like while it's up, even if it's just a small percentage of your total fight time. With Rapid Fire up, you're going to use four Aimed Shots and a Focusing Shot (or 5 Aimed Shots, if you have the Focus) up until 17.2% Haste. At 17.2% Haste or higher, you'll be DPS ahead to delay Chim Shot and squeeze in an extra Aimed Shot.
Another issue that will affect your rotation about 50% of the time is Barrage or Glaive Toss. As they sit right now, neither creates any meaningful breakpoints, so when I need to get off one of these abilities, I'll be using .4 seconds as my guiding number. That is to say, if I have less than .4 seconds left before Chim Shot comes of CD, then it's not worth using another ability and I'll just wait for Chim Shot; if there's more than .4 seconds, then I'll go ahead a cast something else.
As I mentioned when previously talking about this, these little decisions aren't going to have a terribly large impact on your DPS. But, if we're looking to really min-max, to squeeze every last damage out of our rotation, then these numbers will come into play.