I'd disagree on fallen crusader. As a FC you're likely to be tunneled, so being able to death strike or use your cooldowns is a better idea than a 3% heal. I'd suggest Swordshattering or Spellshattering (disarm/silence reduction respectively), or perhaps even dual-wielding for swordbreaking
and spellbreaking if you're facing a team with lots of disarms and silences.
As for the helm, you're missing the fact that it is of a higher ilevel which means more stamina, ahd it has a 270 stamina socket bonus. You're a tank, not a DPS. The neck isn't as much of a gain, but it's still more stamina, which is a stat you can't get enough of (thanks to not using much resilience).
Shoulder enchant should ideally be stamina + resilience for reasons already mentioned, in addition to glove enchant being mastery or haste.
Powerful Primal Diamond - Item - World of Warcraft is the meta they're referring to. It's leaps and bounds ahead of 2% armor in PvP.
You might also consider reforging for a mastery>haste scenario. Parry isn't as good as dodge for a start (you'll have a rune, and a lot of str from gear), and neither stat does any good against casters, whilst haste does. This actually makes the haste/mastery gloves BiS too, although they already were from a stamina point of view.
Final note, your BiS professions are likely Leatherworking and Blacksmithing. Your JWC gets you 160 resilience (that you're not even using), whilst BS gives 320 + 50 = 370 resilience, and LW gives a tremendous amount of increased stamina. As both are great stats for FCs, you'll probably want them
[MENTION=16713]Whatgoesup[/MENTION], the cataclysm belt buckle won't work as it's ilevel 417. If it was 416 it'd be fine, but it's not.