Gas Arrow + Deadly poison support

Hello,

Not exactly a bug report, hesitated to post here or feedback, anyway :

I'm having hard time telling if Deadly poison support gem (-25 % hit, +75% poison magnitude) even work at all on the GAS portion of the gas arrow skill.

When I slot the support, I do see that the estimated poison damage on the arrow hit does indeed go up (Arrow hit isnt even supposed to poison, i do have chance to poison, only gas cloud naturally poisons)

But the GAS cloud poison "damage per second" goes down due to the -25 % Hit part, which leads to my questioning. Absence of DPS dummy made it hard to confirm weither it works or not, still tried to compare poison damage on a single blue mob by removing/readding support, and I had the feeling the poison indeed did more WITHOUT deadly poison support.

Anybody cares to enlighten me?