I feel a starting T5/T6/SWP EP set would be of more value, primarily due to the fact that once you're kitted out in best in slot for a certain tier, there are no upgrades for you from that tier. So why would EP matter, as it's a system used to make gear choices? Additionally, very few people are lucky enough drop-wise to get best in slot for every item slot, so I'm not sure best of tier level X EP values would be accurate for the majority of raiding shaman.

Granted, there'll be some overlap. E.g., beginning T6 EP would be equivalent or near equivalent to end T5 EP, and so on for the other tier level changes. And if you're not going to craft your own EP values, a set of EP that's forward-looking seems the more logical set of values to use.

The obvious caveat being that you shouldn't be a lazy sumbitch and use the damn sim yourself. Kids these days, and other such cliche grumblings of old people.

I wouldn't call it a monkey wrench perhaps, but the badge/pvp gear does cause a problem when we're trying to stratify things into neat little segments of gear. That's one of the reasons that a couple months ago I was asking if maybe we were missing some hidden relationship behind the interaction of our stats that would lead to the "grand unified EP theory."

On the topic of how to define the tiers: the general challenge is that there are two competing objectives: first, figuring out what's best in slot, and second, figuring out how to get there. To answer the first question, one needs to score stuff based on best possible gear; to answer the second, you want to score based on current gear so you know what your largest available upgrades are. Depending on the exact gear in question, these weightings may be pretty similar... or not.

Now, my experience in Sunwell is that for most classes, the upgrades are pretty clear. There are exceptions, to be sure, but for the most part it's pretty obvious what the best item is going to be; thus, since the answer to the first question is easy, I might weight to make the second is easy as possible. The problem being, of course, that everyone has different current gear. But I think it's safe to say that at the current time, the most common instance of a "T6 shaman" is one that has finished BT and farmed it a bit, but has very few if any pieces of Sunwell gear. Thus, I would probably base T6 rankings off end-BT gear with maybe a piece or two of early Sunwell loot (in particular, with 3 T6 tokens dropping off each of the first 3 bosses, it generally doesn't take too long for people to get one or two of the Sunwell T6 pieces).

The other problem you're going to run into is that the weighting of stats (at least for rogues, and I assume shaman are similar) tends to be fairly sensitive to exactly what stats you have at current. If you already have a lot of Armor Penetration gear, ArPen tends to be relatively more valuable; if you have a lot of Str/AP, that tends to make all the other stats (crit, hit, haste, ArPen) relatively more valuable. This is the reason for spreadsheets, of course - to figure it out specific to where in the parameter space you're currently located. Since shaman mechanics have so far defied spreadsheet-ification, you need to be at least a little bit careful about how you define your gear sets - rather than linking them specifically to a set of items, you might be better off using some base set of stats that has a quantity of each stat that's intermediate in the typical ranges of that stat for the relevant gear level. For instance, if a shaman at a given gear level has reasonable gearing options that put him anywhere between 0 and 500 ArPen... I might pick 250, even in no real set of gear actually gives that amount.

I think using the "end set" you'd get from a particular raiding level would be best, so you know what you have to work towards.

However, I think certain assumptions need to be made (and I will most likely use these for Elemental as well).

Pre-T4: No badge gear, no raid gear, no heroic gear.
T4: Kara/Gruul/Mag, badge gear that costs less than 50 badges, heroics, primal nether craftables
T5: TK/SSC, badge gear that costs less than 75 badges, ZA, nether vortex craftables, plus T4
T6: MH/BT, all badge gear, heart of darkness craftables, plus T5
SW: Sunwell gear, sunmote craftables plus T6

BoE recipes for BoP items would be grouped into the instance they drop in.

I think this is a fairly good breakdown based on skill level and item accessibility. It's true that a T4 level player could obtain badge gear that costs more than 50 badges, but the number of badges that player earns per week would be alot lower than what a T5 or T6 player would earn, especially now that all raid bosses drop badges.