2/2 improved judgement

I know conventional wisdom says 1/2 is best for a good 969 rotation, but since my threat is so far above the dps (we're just starting naxx-10), wouldn't 2/2 be better for more libram of obstruction uptime?

At what point does dps threat catch up to the point where I really need to consider being efficient in my rotation?

Having 2/2 Improved Judgement is useless as you still can't cast each judgement until 9 seconds after the last one due to your 969 rotation. Even though it will be up one second sooner, you won't be able to cast it because there will still be one more second left on the global cooldown. 1/5 Reckoning is better than the second point of improved judgements.

Your uptime would go from 55.6% to 62.5%. For a net gain of 6.9% uptime. This gives you a realistic over time benefit of 32.6 BV.

While it isn't a terrible idea that is situationally suboptimal, it can be of great help in AOE fights or fights where your tank dps isn't helpful or needed.