Any reason why poison magnitude seemingly doesn't increase DoT from Poisonburst Arrow?

Is the skill window bugged, or is it because Poison Burst is considered a secondary effect of Poisonburst Arrow, which I don't inflict myself?

It's almost as if magnitude doesn't do anything. It's not listed in any skill calcs/stats. You can pick up that and poison on hit in the passive and support skills but there's no tally or anything on the character nor skills.

added the -25% hit +75% on skill support gem only seems to negate damage of both cloud and hit by exactly 25%.

I thought maybe magnitude is only on the ailment of poison and not just poison damage, but that isn't listed anywhere. I get that it's calculated off of last hit, but there's not even a base representation of it on skills.

Like for gas arrow, does poison on hit mean that if i hit with physical damage only (like the initial hit of the arrow) that it can poison? or does it mean the gas from the gas arrow has will poison more often.

I've overly confused with poison damage and poison ailment.
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- poison on hit, sounds like any physical hit can poison.
- magnitude sounds like the ailment of poison but that's not listed anywhere.

- it's bad enough that I already feel like a gradual glass cannon in 14s. I don't even know how much damage I'm outputting or working towards. It'd be great if the skills can check character sheet for the +1 to applications to show that estimated damage as well..