Ah yeah, you're right. I just saw what I did wrong with my own calculation.

Yeah, you're right. If a tick goes off, then it will be more potency. Either way, my point still stands. The balls should not live more than 4 GCDs with 2 people attacking it, or long enough for that last tick to hit.W hen you apply Chaos Thrust, there's a 1.265s delay before the DoT is registered on the mob. 1.135s later, your 4th hit should be going off, at which point it should be dead (or overkilled). That's 1.135/3 = 37.833% chance of a Tick going off in between the CT -> 4th window. So if you want to play with 42% chance odd of getting higher potency, that's your choice.