I managed to squeeze in a few cycles in between other priorities, and spent some time today on the concept of rebuilding Fire At Will.
Bad News: (?)
Based on a series of tests I just performed, Fire at Will appears to completely inherit Accuracy stats from both the Captain, and any associated items.
I know a few folks here have run parses of combat logs, and performed tests of their own. Care to lend a hand in reproducing the reported Fire at Will issue? Because according to the steps I just took, there is no bug.
Here's how I was testing:
1) Give an NPC a +1000 Defense buff.
2) Fire at Will, and observe the miss-tastic light show.
3) Give myself a +1000 Accuracy buff (power-based, and equipment-based, in separate tests)
4) Fire at Will, and observe nearly every shot land as if neither of the above buffs were in place.
CONCLUSION: Fire at Will is using player and equipment Accuracy boosts when calculating its chance to hit.