Parry...

[bokchoykn]

Turn 6, the highest Accuracy I've missed at was 485. I learned T6 at 490 and did not miss (5000+ Swings). Another tank said he parsed a miss at 489 but this is second hand info.

Turn 7, the highest Accuracy I've missed at was 490. I learned T7 at 492 and did not miss (6000+ Swings).

Turn 8, the highest Accuracy I've missed at was 510. I have never missed at 512 but the sample size was small (1000+ Swings) because I eventually switched to Monk once we decided that two-tank is not what we wanted to do. Our Paladin tanked it at 514 and hasn't missed.

Turn 9, I haven't missed at 516, but we haven't spent a lot of time in there yet (lost a week of progress to Easter family aggro). Blue Garter's tank, Cortana, said he tanked it for a while at 515 without any misses.

Based on the above, I would guess that the Tank Accuracy caps for the above are:

T6: 490
T7: 491-492
T8: 512-514
T9: 515