Originally Posted by
maizensh
I don't get it as that still contradicts the tooltip.
What would make sense is that icicle damage is computed with the debuff (from the final damage that landed on the target), and no further modifications are applied on the icicles to stop double dipping. So the 20% is applied only once, but during the creation of the icicle rather than on its hit.
That also makes more sense because icicles can't crit or miss.
Either way, I'll check it sometime later to verify whether it's true or not.