In current tier gear yes, you want Crit. But in PvP gear (with the lower ilvl weapon being a big factor) Strength is better. Add in the other reasons (NS, BB IT, multi-target diseases) and it's not really a talking point to be honest.
People will end up copying whoever is at the top anyways. I've faced Revolutio several times and he deals insane pressure. And his set up? Full Strength gems, even ignoring socket bonuses, Mastery = Haste > Crit. Mes, our DK hero, is full Str gems as well, only using Str /PvP Power to match glove and belt bonus, then going Crit = Mastery > Haste.
It's not really a set in stone stat weight because DKs have a lot of variables in PvP and even then it's only a minimal change in playstyle. I just had to call out gemming Crit as a terrible idea.
I'm referring to the "Even above hit" comment. The idea that 1 str is better than 2 hit when you're under hit cap is false - even in low ilvl gear. Also keep in mind grievous is still 522 which is the same as last tier's normal pve gear where str was barely 2x better than the secondary stats and certainly not better than hit.
Those dks you mentioned are still using primarily 496 gear. Stats scale differently with gear so it makes sense that we try and figure out what's best for grievous gear.
On crit: crit is attractive because of crit soul reapers and potential burst. DK's are already good at spread pressure, and consistent pressure, so skewing your gear for finishing someone off makes sense. In PvP gearing to cover your weaknesses can be a good approach, but that can mean lower sim dps, lower damage overall or whatever other downside that comes with it. People are way too often driven by a pve mindset where optimizing damage is the only way.
For example with haste gearing: I'm not convinced being gcd capped and having more resources than I can use is a bad thing. If I have an excessive influx of resources it means for every GCD I have multiple options and it also means I have a pool of resources available if something goes wrong or I fuck up.
Forumz tried a high crit set and liked it - now he's running sims to see if his preference is justified. To trash that based on conjecture and having glanced over EJ posts a couple times isn't useful to anyone.