My initial testing was to do this: Use a level 25 lantern (I use Enchanted Lantern
with these 3 abilities - Beam
against Dusty (Whispering Pandaren Spirit's 1st pet).
Open with Flash, as long as you are not slept by Moth Dust it will reduce his hit chance by 50% for 2 rounds. And if you use an add-on to show enemy moves the tooltip even shows that Moth Balls has a 0% hit chance and Cocoon Strike has a 50% hit chance. Now you Beam (hits his cocoon) and check the tooltips again and Moth Balls still has a 0% hit chance. Yet he still hits anywhere from 2-4 times every time.
If the mechanics actually worked you should be able to do Flash > Beam > Beam > Soul Ward > repeat. And the only attack you should take damage from is the 50% hit chance cocoon strike. Instead of the massive destruction by 0% hit chance moth balls.
Additional testing has shown that in PvP pet battles (with a guild mate) that other abilities reduced to a 0% hit chance still hit far too often (Moth Balls being the best test, hitting 2-4 times out of 5 shots, with a 0% hit chance). Going to have to update my bug report since this is more than just Dusty being a PITA (which is why I was trying other methods in the first place).