Let me clarify my post, I run the latest version of RAWR on my DKDPS and look at posible upgrades for certain gear, depending on the gemming combination there at at least 2 possible entries on the list. One will be gemming everything with Bold Cardinal Ruby to maximize strentgh and another one that includes stamina or something else, which seems a better option since the numbers are higher than the strenght option one.
The question comes to my mind because in the forum under DK the suggestion is to gem everything with strenght
which seems to me contradicts what RWAR is suggesting.
You should never get better numbers with a +stam gem.
You might get a better result by swapping a single +20 str gem to a +10 str/+10 crit gem, if it will trigger a +6 str socket bonus, effectively making it a trade of 4 str for 10 crit rating.
This is why you sometimes see the "matching socket bonus" option providing more dps than the "pure str" option.
Yeah, getting your meta activated is sometimes worth more than the DPS bump given by going raw red gems. So while a pure blue +stam isn't the best option, it would be better than a broken meta. As mentioned above, use a Nightmare Tear or a dual-colored that would make sure your meta activates.