Actually, I think you're talking out your ass. Every stat weight I can find for Unholy has Str almost 2.5x multistrike, your second best.
Noxxic definitely has STR at 2.5x Multistrike.
Except Noxxic is garbage.
You shouldn't be using a set of gear-irrelevant stat-weights, and rather be actively simming/testing your character, as values change based on gear level. Strength is still your best stat, but it's not best-stat enough to justify giving up 100 of top-tier secondary for 10-20 strength. For BiS simming for T17, Spoonybard has some good infodumps and runs updated tests frequently. At Highmaul Mythic Gear ilvl, strength's impact on DPS is less than double your secondary stat's impact, while Multi and Mastery are still nearly double or more the impact of shit like Versatility and Haste (Before factoring in that, as a melee, Haste actually performs worse in real life than it sims at a higher disparity than the other stats).
On the plus side, SimC-derived runs were valuing Mastery too highly due to a coding issue allowing it to double dip on Scourge Strike, so on ST, Mastery's weights should be down closer to Crit now, making the Multi/Crit gear more appealing than previously.
Also, RE: MOP Primary VS Secondary balance. People didn't gem primary stat (and several class still *did* at multiple points in the patch cycle), because Primary Stat *gems* had half the stats of Secondary Stat gems, in a direct bid by Blizzard to get people to stop gemming straight primary stats; not because the primary stat itself was worse than the secondary stat on a point per point basis.
As a Windwalker Monk in MoP, our gemming oscillated from Mastery/Crit Gems (Major mastery tuning during the first tier lead to some flopping), to Magical Technicolor Gem Coat in ToT (Rune of Reorigination wonderfun stat balancing), to Pure Agi Gems in SoO (Being at 100% crit chance with Windsong procs before factoring in Gems was mildly amusing).
There is a DK spec where you just straight up equip your highest ilvl piece of gear though! 2handed Frost, The Spec That Refuses To Scale.