Is the passive 'Stormbreaker' working?

I have Stormbreaker in a Megalomaniac, but I feel like if it isn't working.

Im fighting Xesht and i'm using Ice Shot. But im also giving the other 2 elemental damage, but I don't feel like he is taking 20... 40 or even 60% more damage from ailments.
To be honest, my hits almost feel the same as without Stormbreaker.

So, is this passive really working?

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seaman#4993 wrote:

This isn't more damage, but increased damage. All applicable sources of increased damage stack additively. So, with 60% increased damage, the total damage increase could be 5-10%.

Hmmm...