What is increased duration?

If I do 100 bleed damage over 3 seconds, then I get a buff for +100% increased bleed duration, does it make it 100 damage over 6 seconds, therefore weakening the effect?

Side question: does DoT on weapon damage trigger life steal? Thanks!

dmg/s remains same, it used to be like what you said in Titan Quest

meaning 200 damage over 6 seconds?

Yup, damage per second stays the same, it just lasts longer. Increased duration is mostly relevant in that you don’t need to reapply the effect as often.

Since DoTs of the same type stack, the question is no longer how often you need to re-apply, but how big of a stack you can rack up to drive the enemy’s health into the ground.

Do note also, that if your enemy has reflect, your reflected DoTs will have your prolonged duration, and can be quite nasty (my WitchHunter has DoTs for 30+ seconds on him)

As evidenced by this