You're probably right.

Though things are quite complicated, and I'd like to present my findings so far. Maybe someone else will have an idea and work further on this. First and foremost, you have to consider: For 1% Crit, you get about 1.40% Haste. Crit has to make up for this in yielding dps at points where Haste doesn't yield any.

This is what I came up with:

These are the things 1% Haste will give the same dps boost as 1% Crit, given current Haste = current Crit.
- Autoshot dps
- Pet autoattack dps
- SS dps
- Cobra Shot dps
- Culling of the herd proccs
- GFTT proccs

Things only affected by Haste:
- Focus regen. We'll have to see below to how much damage this amounts
- Speed of Rabid stacking up (I guess this is neglectable)

Only affected by Crit (and Mastery):
- Damage from ExS / BA
- Kill Shot damage
- DPS a point of focus yields.
- Pet yellow damage

At last, Sic 'Em is affected by both, but not equally.

Now, if you compare only the Haste section with the Crit section, Crit is far ahead.

Assuming 1% additional focus overall from 1% Haste, because CoS casts faster as well, you can convert the additional focus like this:

AS costs 22 focus and glyphed does 1.12*(WD + 0.242*RAP + 252)*Crit*Mastery.
Every additional point of focus we get will be dumped into AS. So for every of those additional points we get:
Crit * Mastery * (0.051*WD + 0.01232*RAP + 12.82)

1% Haste amounts to 0.04 focus every second, so by multiplying by 0.04 we get the dps gain per 1% Haste:
Crit * Mastery * (0.00204*WD + 0.0004928*RAP + 0.5128)

We can extract the RAP part from the WD part (I guess this is normalized to 2.8 weapon speed) like this: WD = 2.8*WDPS + RAP/39.2 to get a formula tuned towards the most important aspect (which is RAP scaling, I guess):
Crit * Mastery * (0.005712*WDPS + 0.000544840816*RAP + 0.5128)


While Crit gains us:
ExS:
Damage glyphed: Mastery * Crit+0.06 * (RAP*0.819 + 1359)

This is were the diminishing returns of Crit come in. Because Crits can't crit, the actual part affected by one's critchance is in fact Mastery*(RAP*0.819 + 1359).

We take it for granted that we get one ExS every 6sec. Therefor dps gain is:
Mastery * (RAP*0.1365 + 226,5) * 0.01 = Mastery * (RAP*0.001365 + 2.265)


And now for BA:
Damage: Mastery * Crit * 1.30 * (5*0.112*RAP + 2395)

Suppose we fire this every 24 seconds, then 1% Crit yields:
Mastery * (0.0003033352*RAP + 1.29838299) * 0.01 dps = Mastery * (0.000003033352*RAP + 0.0129838299)


And yellow pet damage:
Crit * (186 + ((RAP * 0.40) * 0.20))

Cast every three seconds, 1% Crit leads to a dps increase amounting to:
(0.62 + RAP*0.0002667) * 0.01 = (0.0062 + RAP*0.000002667)


Combining everything Crit brings to the table:
Mastery * (RAP*0.00136803335 + 2.27798383) + 0.0062 + RAP*0.000002667

So, to even out the RP scaling, Crit would have to be 151%, which is obviously impossible. But we have to consider that the value of Crit will also rise with every %Haste we already have, because the additional focus will be converted into AS', which are able to crit.

Once again, though, we first have to acknowlede that Haste is cheaper.

Crit * Mastery * (0.005712*WDPS + 0.000544840816*RAP + 0.5128) * 1.40 = Crit * Mastery * (0.0079968*WDPS + 0.000762777142*RAP + 0.71792)

Now, if Haste wouldn't be more effective in the aforementioned regards, we'd need 79% Crit for 0%->1% Haste to be more effective than an additional percent of critchance. After gaining that one percent, Crit would probably ahead again, because of its scaling with the additional focus.

But we know that there is a portion of our damage, where one point of Haste rating is 40% more effective than one point of Crit rating. So let's say we have one portion where Haste yields 40% more damage and one portion where Crit yields 80% more damage (I'm actually too tired right now to comprehend whether this is a feasible approach).

The decicive question obviously is: How much of our damage has to stem from Haste-affected damage sources for Haste to be better?
Setting 1.40*X = 1.80*(1-X), we get X = 0.5625%, meaning ExS+BA would have to make for less than 43.75% of one's damage for Haste to be more effective. This is for equal percentages, though. If you already have 30% more Crit than Haste, the portion of your damage made up by ExS and BA will obviously already be larger.

Anyways, this is just a first approach. There are many things still not taken into account. Many open matters:
- Crit also scaling with Haste
- There already being spare focus which Crit affects through the AS'
- WDPS part of Haste
- Kill Shot damage portion
- TotH yielding even more focus on more AS' being fired
- Sic 'Em - does it matter?
- What is the dps cost of delaying ExS? What are the sweet spots of Haste, if we also take this into account?
- What role does Mastery play in all this?
- Most importantly: What are the respective breaking points, where one stat takes over another one? Or what are ideal ratios?

Edit: What the guy below me said. SS also has to be included into the section of things only affected by Crit, while not by Haste then in my above post.

That's Warlocks. Haste doesn't affect Hunter Dot ticks at all.

Of these things, only Autoshot and pet autoattack is increased. Mentioning GftT here is "double dipping" really, as they are only increased because autoshots are increased, CotH is not affected in any way by haste, but it IS affected by crit - CotH triggers from pets basic attacks which are on a 3 second CD, not affected by haste. As others have already said hunter dots are not affected by haste, and there is no increase in CoS damage from haste except at specific thresholds which allow you to fire off either 1 more CoS (casttime threshold) or 1 more AS (focus regen threshold), so 1% haste does not increase CoS dps at all.

Oh, you're right. The terminology used in regards to pet "basic attacks" is kinda confusing. I don't see what you want to say about GFTT, though. If GFTT was triggered by all hits, not only by crits, Haste would give us more GFTT proccs, while Crit wouldn't. So it's worth mentioning in this regard, I think.

I'm not denying Haste has certain thresholds where it is more effective. Yet, we still don't know whether it might be worth it to go for these thresholds, and we also don't know about the viability of Haste outside of these thresholds aka whether a delayed ExS can be worth it. At least, I haven't seen any math on it in this thread and there is nothing certain mentioned in the OP.

For example, consider a CoS with casttime 1.4. Four of those and an instant beetween every two ExS would lead to a ExS delay of 0.6 seconds, leading to us casting 10% less ExS on average. We get ~40% more CoS dps, though, which also leads to more focus, resulting in more AS. I personally can't see at a glance whether this would be a worthy tradeoff.

edit:
Alright, example failed, but I think it still convays my point.

I reported this as a bug, since CoS cast after SrS applied by Serpent spread doesn't benefit from the +10% dmg (noxious sting talent) but autoshot does. Also, Multishots add the duration of the serpent spread, with 1/2, we can have a 7+ sec SrS.

Moreover, when SrS manually, and the sting is ,say, 12 sec left, if I multishot (1/2 serpent spread) the SrS duration is brought down to 6.

You have the math wrong here. 4 shots of 1.4 seconds 5.6 seconds, add an instant and its 6.6 seconds, then you can fire ExS, for a total delay of 1.6 seconds (the cooldown starts on cast, not on the end of the GCD) - to fire off ExS on CD you have 5 seconds to fill between.

The fact that Claws of Agony have strength rather than agility, make it a clear dps loss to any decent agility weapon.

Actually it's not Multishot, but Serpent Spread. The latter does not refresh or increase duration of serpent spreads, but sets up new serpent sting with 6 or 9 seconds duration. As of stings nature, old one is instantly gone.

After some extensive gear shuffling with Zeherah's I'm finding a lot of the new enchants being lackluster in comparison to WotLK enchants.
[Enchant Cloak - Major Agility]
[Scroll of Enchant Bracers - Greater Assault]
[Enchant Gloves - Major Agility]
Are all better than the available rating-based Cataclysm options. For bracers [Draconic Embossment - Agility] (130 Agility) is obviously better by leaps and bounds and makes leatherworking the strongest Hunter profession by far.

Also I was tinkering around with gemming options and found [Relentless Earthsiege Diamond] to be superior to both [Chaotic Shadowspirit Diamond] and [Destructive Shadowspirit Diamond] with respective gemming to meet the requirements. I can't imagine that downgrading content to this extent is intended.

Short answer: It's because of all raid buffs that give you more crit.

Long answer:
This is how I think when I am about to balance crit and mastery. I use the 100 shots model with each shot dealing 100 damage, and my current crit is 19% unbuffed, but in raids fully buffed with flask, agi food, 5% crit buff, horn of winter buff etc. I get about 29.5% crit. My current mastery is about 16.5%. And according to world of logs, my elemental damage is 80% and my physical damage is 20%.

So my combined crit and mastery is 46% and if i use the 100 shots model i get (100*100+x*100)(0.2+0.8*((46-x)/100+1)) and by using the derivative of that i get x~=35.5. So according to this i should balance my crit to 35.5% and that would give me a mastery of 10.5%

But if i analyze the formula above in my graph calculator i can see that anything from x=29 to x=40 gives really good result. So approximately 4/6 to 5/6 of total mastery+crit should be crit and 2/6 to 1/6 should be mastery. And from here it starts to get really interesting because glyph of es gives you 6% more crit to es. So for es i have 46%+6%=52% total mastery+crit to balance.

So if i now should balance 52% with explosive shot only (remember 100% elemental damage) i get (100*100+x*100)(1*((52-x)/100+1)) and as said before in this thread to get the best result x should now be half of 52, x=26. But once again analyzing the graph in my calculator i can see that anything from x=19 to x=33 gives really good result, or approximately 1/3 to 2/3 crit/mastery.

So for my current gear/stats choice i take from both worlds, I know I get really good result for explosive shot with as low as 1/3 mastery. And for my overall damage i get really good result with as high as 1/3 mastery. And to achieve this balance i need a lot more mastery rating then crit rating on my gear.