After seeing how the puppetmaster type levelled slow due to lack of direct damage, I thought I'd try playing a persuasive poisoner. Unfortunately, you gain 0 exp for the poison damage -- if you gain exp for dealing any other damage type, why not poison? What's worse, you don't get exp for making the kill with poison!
Didn't know that, but it sucks. If it was up to me, XP should be awarded depending on how creative the kill was, and poison is certainly an imaginative way of putting someone in the position where they'd be pushing up envenomed daisies.
I thought it was creative, and fun; slip 'em a dose, cast insect swarm on 'em and casually stroll away. But getting no advancement took the wind out of that and made me wonder whether you're being cheated out of exp by using poison on a weapon; if you'd get less exp with poisoned strikes than pure physical, charged or pyro weapons. That's kind of imbalanced considering how you're left at risk while the poison works, whereas the other damage types act instantly.
Maybe, but dynamite works in one shot. Sure, the target will be upset when you plant it, and may still be upset after it kills them but at least they'll stop expressing their irritation. Walking in circles while watching someone slowly die in a cloud of gnats was only fun for the first couple seconds (if only Entangle worked while they're taking damage), and when it was finally over I had nothing to show for it but a bug-eaten carcass.