As of current I disagree with the TC arguments above. I would much rather use the two talent points in Totemic Focus and get a longer tide, which doesn’t bind me to dpsing while I should be healing. Yes, there are some, I would say fewer rather than more, fights that do have some down time for healers. Again however, I disagree. I think that many people are looking at the mana gain on the charts and forgetting that in order to make that mana they had to spend mana. Let take this example of 5 Lightning Bolts:

5 x Lightning bolt = ~7500 mana
Lets say that one misses because we have no hit.
Lets assume that one crits and the rest don’t.
Lets give it a moderate value of 9k per crit and 6k per non-crit.
27k dmg = ~10k mana – ~7500 mana spent = ~2500 mana gain and 10-15 seconds lost. (Using an average ilvl of 355. Obviously there will be greater returns on higher ilvl gear)

As of current, I can pop my trinkets and then throw down mana tide with Totemic Focus x2 and restore 40-50% of my base mana (~37,000 – 41,000 mana) and it didn’t cost me a thing. Because fights are so long we have time for at least 2 tides if you use your first one early on at 70% or so. More importantly, I never have to stop healing. My usual activity time is 100% and I normally come in top or second highest heals. Also, without Totemic Focus (as of current) you most likely have to replace your totems because they’ll expire under current raid conditions. This comes at a cost of ~6k mana.

Furthermore, if we take the mana restored by tide divide it by the 3 min cooldown and multiply it by the 10 seconds it took equal to casting the lightning bolts we come up with ~2270 mana per 10 seconds which is a little less than that from TC, but without the loss of time and assuming that you can dps the entire fight, which is impossible.

Now this is all under the assumption that you removed the 2 talent points from Totemic Focus. I would only assume that the other consideration would have been to take the 2 points from Ancestral Swiftness, which I personally use and love. I have seen some shamans take it from Acuity which I disagree on as my crit unbuffed is 20% and ELW is my third top heal behind HR and CH.

The popularized 25man TC spec does include totemic focus, as group utility is the whole basis of the spec. This is the approximate spec that is being used:

TC/Elemental Precision spec

Improved water shield is dropped as the spec assumes you are running haste not crit, reducing the value of water shield procs. Improved cleansing waters is also dropped as the usefulness of this in a 25man raid environment is negligable; there are other classes which can handle magic dispells. Mana Tide Totem is used to bolster the regen of priests primarily and paladins secondarily, and TC is intended to bridge the gap for your personal regen, allowing you to keep up a HR/CH raidhealing rotation.

This spec is purely intended for 25man use however.

I beg to differ that this spec is "popularized" for any level of raiding. It's a paragon spec that assumes that you are only doing 25 mans, have the best healers in the game pared with the best gear. A very unlikely situation for 95%+ of the raiding community. I have never seen this spec used on anyone outside of a very select few on forums. Out of the 3 paragon resto shamans only one uses the spec as it's intended with continuous HR while the others use traditional healing methods. This is also shown in the number of LB's cast by the other 2 paragon resto shamans, some fights as little as 5. The overhealing performed by these shamans using this spec is normally in the 55-65% range with an average HPS of 8k assuming top level gear. Most resto shamans who don't use this spec are ~500 hps less with far inferior gear. In addition it I agree 100% with the below quote that it essentially makes us "brute force" healers.

A quote from lifeingroup5.com:

"... I have some concern about how it might influence the future of shaman healing. Not only does it highlight the current misalignment of philosophy and application of Telluric Currents, but it also puts into stark contrast the tension that exists in shaman healing. And while the former condition is easily addressed in the form of a TC nerf, the latter condition is not as easily handled. Because HR is such a high HPS spell, with a small limiting CD, resto shamans will naturally try to cast the spell more frequently, as their mana will allow, in an effort to increase their healing contribution. Should the limits on mana become imbalanced (as they are with TC usage), then the spell will become a new 1-button to victory, casually disregarding qualities like selection, judgment and overhealing in favor of a brute force approach. This is not a direction I care to see shamans go, and it’s hopefully something that the watchful eyes at Blizzard have on their radar."

The spec doesn't require a particularly optimized setup or particularly great gear. It's a 25man spec, and it will work just fine on normal modes, however there is little need for optimizing tide or extending your mana pool in normal modes. For hard modes, contrary to what you suggest, it helps ease the tension on less well geared Shamans mana pools, allowing them to occasionally replenish them through LB spam. It does not diminish your output one bit (I've ran a bit under 20k sustained throughput with this spec on hard modes), as it does not give up any healing potential for the added utility. The only reason you'd see this spec healing less than usual is because it can function as a reliable range interrupter, which given that Paragon seldom runs with Shamans otherwise, is probably part of the role for them.

The primary reason I'd see for Paragon not running this spec any longer on most of their Shamans is in fact that they have to some extent out-geared the need for it.

Ideological concerns don't matter here. This is about what works, and what doesn't, and under what circumstances.

A wild guess is 25mans, some fights like Chimaeron and Maloriak will however push ES up alot thanks to HR and CH proccing all over.

I usually get (everything 10m normal modes) EL to be:

Magmaw 11%
Nefarian 12%
Chimaeron 21%
Cho'gall 11%

of my total healing. So the 30-40% range ist most likely due to the nature of Shaman Healing in 25m with HR and CH being a big part of your time spent casting and producing quite a lot of overheal thus proccing EL but not contributing that much to your overall healing as expected.

Did you spec 2/2 Blessing of the Eternals? & how often do you use Chain Heal? Chain Heal was changed so that EL only has 25% of the normal chance to proc & w/ 2/2 Blessings there is a 5% chance to proc EL on targets above 35% health and a 21.25% chance to proc on targets below 35% health. Also using Healing Rain (preferably on a larger size group-maybe your melee & tanks) will also proc EL but on a much lower scale. So definitely find out what content of a raid they are doing. 25 or 10.

I don't have access to a Jar, but Tsunami appears not to:

I had 2746 spirit with 5 stacks of Tsunami before MTT, 13730 with it up and 5 stacks, then after removing the 5 stacks I had 13330, meaning it only adds 400, not 400% of the 400 buff.

Taking your evidence at face value, it is affecting it. The way Mana Tide works is that it takes a snapshot of the eligible spirit you have and creates a buff that is 400% of that snapshot. It doesn't dynamically update if your spirit changes while it is up.

Using your numbers, if you have 2746, including 5 stacks, you get a buff of 4*2746 = 10904. Adding 10904 to your existing 2746 = 13730. When you click off your stacks, you'd expect it to only change based on how much you removed, not 400% of the removed amount.

EDIT: I'll check the Jar when I get home in a few hours. I don't have the 4pc bonus to test it as I'm main spec Elemental. It wasn't working on the PTR, no reason to think they changed that, but worth getting the question out of the way.

I had "increased by 8788" with absolutely no buffs. (the tooltip on the MTT buff, not my spirit)

I waited for my CD...

I then stacked my Tsunami to 5 and i had "increased by 10338" (again it is based off of MTT tooltip, not my spirit)

This means that Tsunami does in fact work with MTT.

Any news on the Jar?

The short term spirit buffs won't provide mana to your other party members; mana tide will only look at your spirit without the buffs when buffing them.

Unless my friend was reading his spirit wrong, I think this is what the re-design of MTT meant.

Tested with Blood of Isiset