First to pick a few sentiments at this statement. One there should never be a pure combat dagger rogue as the weapon speeds of daggers just don't match what you need for Mh 2.50 or slower and the drop in your dps is just retarded.

Secondly as a combat rogue you should have both Lethality and Ruthlessness being 15/51/5 spec which Imo is way better than a 7/51/13 spec focusing on rupture damage.

And thirdly as your gear gets better as a combat rogue it becomes ungodly to maintain a 3/5/3-5 rotation being 3snd 5 rupture and 3-5 eviscerate depending on how much snd time is left.

Edit: Adriana do you feel the wording for Lightning Reflexes is indicitive of only affecting HR on gear and from potions making those more powerfull then they are now or is it more closely related to 10% base speed on your character?

I think he means "combat dagger" in the sense that he is using the old school dagger attack of "backstab" rather than SS...

In which case, while daggers max out at 1.8spd (I can't think of a 1.9spd current weapon), the way backstab is calculated takes that into account so that overall BS damage is similar to SS damage.

What? You do know combat daggers uses backstab instead of sinister strike for combo point generation correct? I hit close to 5k dps combat dagger spec'd on patch last week, and with todays changes, I anticipate it going up a bit. You may need to add opportunity into your combat dagger build as well.

This same question has been asked over the years about a rather large number of effects modifiying haste, crit, and even hit. So far, the only effect yet seen in-game for any of them is the naive one, an additive X% of that stat. As far as I'm aware, the Deathknight STR->Parry thing is the only class talent or ability to ever interact with ratings, and even that adds to the rating statistic, it does not mutiply or otherwise modify it. It is an extremely safe bet to say that the talent simply adds 10% haste.

Note that all sources of haste multiply (all haste rating counting as one source), so this does impact the value of haste potions and suchlike, but no more or less than any other speed or damage increase. In particular, it does not change the relative value of these effects compared to alternatives.

Nitpicking here, but it's not "haste off" your weapon speed; This is misleading. With the SnD buff (at 40%), you will perform 7.7% more attacks over the same period of time than you would pre-patch (at 30%).
The haste from SnD is then multiplicative with haste from your gear.

A whack thought just arose in my mind, seeing this new free haste on SnD, and providing that LR still stays at 10% haste.

Combat builds will have severe difficulty doing a SnD/R rotation. The energy overflow from Combat Potency could very well push you deep into a xS/yR/zE rotation( which is happening already sometimes pre 3.0.9). Any thoughts on that?

The idea is to maintain your xS/yR rotation intact, and weave in a zE only when applicable. If at any one time you don't have the time/energy/CP's to weave in your zE while keeping the xS/yR part intact: simply don't do it. The rotation is still called a xS/yR/zE rotation, because it denotes what you'll generally do. But at times you have to track back or downgrade for a few seconds.

I believe that it still is a 10% increase in attacks but a 7.7% increase in white damage. 10% haste will always be 10% more attacks.

Re-read the post you just responded to; he just finished saying that one of the reasons that haste was weak for us was that it does not have any effect on our yellow damage, as it does with casters who have cast times or channeling times for their yellow damage.

Yes, but the reasons he gave for that were as follows:

(1) haste does not lower GCD
(2) our abilities are instants
(3) rogues are not close to the hit cap

Observant people will note that (1) and (2) are actually the same thing, and that none of the three actually have anything to do with why haste does not affect our yellow damage. The reason haste does not affect our yellow damage (modulo second order effects from Combat Potency etc) is that it's limited by our energy income, which the OP didn't mention. GCD, instant cast abilities and hit capping have nothing to do with it. Even if they changed things so that haste did affect the GCD, gave us cast-time spells, and put us at the hit cap, haste would still be a very weak stat for us, because it does not affect our energy regeneration rate.

Yes it's a 7.7% increase in white damage from slice and dice. However you still receive 10% more attacks than pre-patch.