delete please. (previous question amended appropriately)

One DS does more tps than one Heart Strike, however one costs 2 runes versus 1 rune. HS use is the correct priority (unless you needed a heal and DS lands in time, then you get half the heal's amount in threat, however usually healers beat you to it).

Its seems such a simple thing yet I can’t find the answer in black and white anywhere.
How do auto attacks work?

Not so much how do they hit as what determines when and how often they swing?

Are they independent from strikes and spells (since except for AOTD all my spells are instant cast)?

Does haste and presence affect them?

I played around on the dummy a bit and got the impression melee just goes at a set rate independent of strikes etc and that unholy presence does increase the number of swing. Implying that haste would also increase white hits (in blood anyways).

Is this correct?

Another thing I am curious about and lack the knowledge of statistics and hard core math to figure on my own, after melee hit cap for dual wield, 5%, does additional hit increase white damage as a linier function? Or is it a curve of some sort?

Your question could be answered by merely looking at your character panel, or even the abysmal wikis that abound. Haste affects the swing timer, that's practically all it does unless you're casting. You could discover this just by swapping presences and reading your Melee tab. The melee hit cap is not 5% and hit never did increase anything as a linear function. Hit past any cap is pointless in PvE. Hit past the cap in PvP only serves as a mitigation to abilities that increase character resistance or racial resistance, like Cloak of Shadows or the Bloodelf magic resistance racial.

Spell power has absolutely no effect on anything a DK does. Attack power functions like spell power for all our spells.

I did post this in the Rawr thread, but it can be posted here, just in a different degree. It doesn't seem as if that thread is getting a lot of traffic.

I hope this is not a stupid question, I've searched every thread I could think of to search.

I have a DW DK, 0/53/18. I have 4 piece T7. I have enough badges to purchase the T9 shoulders.

Rawr evaluated these shoulders as only a 6 unbuffed DPS upgrade, despite the new shoulders having almost 60 more attack power, more hit, crit, etc. I tried the correct color gem to make sure it was not breaking my meta, and so on.

I assumed the four piece bonus was not that great, but maybe the 4t7 is a lot better than I originally thought. I know I do throw a lot of Frost Strikes out, but since I'm usually capped on RP until I go to dump, I couldn't imagine it making that big of a difference.

Thoughts?

For a Death Knight, which is more important to focus on, strength or agility?

I am aware that haste reduces swing time. Does it also reduce the GCD (provided your not in unholy presence) thus getting an additive effect. (faster swings more often).

How does melee attack frequency work? Is it independent from the global cool down? Is it independent from any strikes and/or spells cast? Does it sit there adding up damage at a pretty set rate despite anything else you might be doing? Or does other activity slow or interrupt white damage?

As for hit, I was unclear, I forgot to mention with respect to dual wielding where the strike hit cap is 5%. The dw melee hit cap being 24%. Does +hit over 5% add more damage in a liner function or with diminishing returns?

As hit gets closer to 24% it seems that the number of misses would start to diminish rapidly at some point. Where is the break in that curve? Or is it a straight line?

Haste reduces the swing time on your white hits. It also reduces the GCD on your spells (IT, BB, PE, DC, DnD) which means that you do get through most rotations at least slightly quicker (e.g. if you are under 200 or so haste it is better to run imp unholy, see the unholy thread for more info).

As far as hit is concerned - you should only focus on getting the 263 hit rating to ensure that you don't miss with special attacks, beyond that hit is far less attractive than other stats (you do however want to get to 13% spell hit including talents, so your spells won't miss). I can't answer to the maths of the curve though.

Unless you cast/do something that resets your swing timer your white attacks will continue while you cast other strikes - I can't speak to which spells reset the swing timer for DKs, apart from any non-instant.

Note that the effects of haste depends a lot on your spec and ability usage. As mentioned, only a few abilities have their GCD reduced, so the effect of haste is increased/decreased by that. For example, Unholy specs that favor DC spam will get a good deal out of haste, whereas a Frost build that uses only one 'spell' every 20 seconds (either Icy touch or Pestilence, depending on IIT or GoD) get practically nothing. When in doubt, use Kahorie's sim I've found to be a good policy

In fact, the critical points are 8% melee, 17% spell and 27% melee.

At 8% (melee hit) 2H and special melee hit is capped. For DW with Nerves of Cold Steel this point is at 5%.
At 17% (spell hit) spell hit is capped. With Improved Faerie Fire / Misery (3%) and Virulence (3%) this point is at 11%. Notice, though, that spell hit scales faster than melee hit, so 11% spell hit equals about 9% melee hit.
At 27% (melee hit) DW autoattacks are capped. With Nerves of Cold Steel this point is at 24%.