PLD BiS (Post T9) - Widely Accepted vs. Optimized Crit

[PROBOUND]

Det > Crit for tanks.
-24 crit, -63 parry, -31 SS, for +78 Det

While i do love your gearset (Seeing a Tank at 300 DET 400+ crit is lovely), i cant help but feel 500 Parry is too low. I cant argue with a T9 clear however. If your MT had 500 Parry or less i'd have to give it up to your healers. I could be wrong though as i dont have any exp in T9.

The only thing i have to go on is what other exp'd tanks recommend.

I brought up this argument to Junep3i (BG's original Twintania clear MT, now with Collision and multiple T9 clears) and he shot it down quite easily and i was only suggesting a loss of -15 parry +64 Crit at the time. He seems to think giving up any amount of parry in a progression scenario is a bad idea regardless of a DPS increase. While i dont like to take the word of any 1 player as Gospel, it seems to be the general concensus of many others as well.

If the +13 Parry/1% calculations are correct, i cant see giving up 8% parry chance/rate being a good idea in favor any amount of DPS gains.

I'd love to hear some other opinions from T9 PLD's who MT as well.