I would say that you are taking some great gloves and replacing them with the weakest of the tier pieces (and at ilvl 219 at that) and taking probably the best legs and doing the same ilvl downgrade. The 4pc bonus probably doesn't make up for the far weaker stats. You didn't say how much agility you lost. Those gloves and legs have insane amounts of agility, and the tier versions just don't.

Now, I may be wrong, and it could be something else, but this is what I saw with the same gloves and Darkcore Leggings (also lots of agi).

There does seem to be something weird going on between Giant's Bane and Magnetized Projective Emitter though. The gear planner always values Giant's Bane higher, but swapping in the Emitter results in higher dps even without swapping out gems for the extra hit rating.

@Kathucka: If changing out your +hit gems for AGI, still leaves you "well over the cap", then why do you still gem for +hit? How much hit do you have when you put on the Surge Needle Ring, since it has 32 +hit?

If you are already above the hit cap by the rest of your gear including +hit gems, and then put on a ring with +hit, it is less good than a ring with all damage stats. After you changed your gems to AGI *and* put on the ring (has 32 +hit), you are still over the cap. With the other ring you wouldn't. That is probably why it can be both, a downgrade and an upgrade, depending on the rest of your gear settings.

Clearly, in Kathucka's situation, he is not "well over the hit cap" prior to equipping the Surge Needle Ring. I presume he has just enough +hit gems to put him to the cap. The point is that equipping the ring (which has +32 hit) allows him to change these few hit gems to agility, remain hit capped, and get a DPS gain, rather than "wasting" the +32 hit rating (since he's already hit capped, albeit through gems).

He was showing an example of why the spreadsheet should at least give the option of counting excess hit as something of value (whether it be the DPS of hit or agility or whatever).

EDIT: mooted.

This is something I'm working on, but it's not trivial to determine which gems can be replaced (I can't just count any points of hit rating over the cap as agility, because they only come in chunks of 8 or 16 on gems) and how they are replaced.

At least it's not trivial to do in plain Excel (VBscript it's doable, but I want to avoid using that since this is supposed to work on the gear planner).

While that is true, just doing it point-for-point would be more accurate than what we have now, and would probably be sufficient imo.

EDIT: To elaborate, doing it point for point would at least give it a good metric for at-a-glance upgrades. Sure, the fact that it might be off by a few DPS due to being off by up to 7 agility might affect the relative position of side-grades, the real concern is being able to correctly identify a solid upgrade (e.g. the Surge Needle Ring example).

But I agree, if you want to model it very accurately, it is very nontrivial, as it becomes an optimization problem (since you need to take into account possible socket bonuses, the effect of removing an enchant like Icewalker, etc), and optimization problems aren't really what the spreadsheet is built for.

TL;DR: Point-for-point is easy and gives relatively good at-a-glance results. Modeling the exchange of individual gems is (potentially very) difficult but gives more accurate numbers.

Because if you are not using the +hit on the MPE, the others are simply better.

Comparison:

SC vs MPE (16 Agi in socket)
-7 Agi
+25 Crit
+22 Haste
-20 AP

I think the crit and haste outweigh the AP and Agi

GB vs MPE (16 Agi in socket)
+21 ArP
+27 Haste
-7 Agi
-20 AP

The Arp and haste outweigh the Agi and AP by even more

Without using the hit on the MPE, the others are simply better.

My guess is that with these particular latency values and your haste rating, the shot rotation is lining up slightly differently. This has a similar effect to waiting for a higher-DPS shot, for some latency/haste combinations.

On the other side though, if you are using the +hit, then the MPE is better. For instance, if the 27 hit was used to replace 24 hit rating in gems with 24 agility, then the differences are:

SC vs MPE (16 Agi in socket)
-31 Agi
+25 Crit
+22 Haste
-20 AP

GB vs MPE (16 Agi in socket)
+21 ArP
+27 Haste
-31 Agi
-20 AP

31 more agility is a big deal since that is really 35.5 agility with CE and BoK. This equates to about 39 AP and 0.42% crit. Thus:

SC vs. MPE
-59 AP
+0.13% crit
+22 haste

GB vs. MPE
+21 ArP
+27 haste
- 59 AP
- 0.42% crit

Hence, although I have both GB and MPE, I use the MPE since it allows me to replace hit in other places for more DPS.

89g: [Band of Lights] is classified as an Ulduar-25 drop. According to Wowhead comments, this item actually drops from Algalon-10, which would be Ulduar-10 Hard.