is fire dot multiplier any better than burning damage?

[Dikshit Koomar]

still not sure why this was changed

[Mindtroverted]

Multipliers on the skill tree only apply to critical hits, AFAIK. Meaning that a fire dot multiplier will only be useful if:

1) You have a high enough crit chance
2) The skill you are using can crit and either deals DoT dmg or can Ignite

Burning damage covers more types of builds since burning includes certain spells, as well as Ignite. You don't need crit to make use of burning dmg nodes and it works with stuff like Righteous Fire and other spells.

[Dikshit Koomar]

they converted all of the burning damage nodes to fire multiplier though

[Mindtroverted]

After doing a bit more research, it seems that dot multiplier has nothing to do with crits. DoT multiplier does what its name implies. It multiplies the dmg of your DoT. So if you have a total of +35% DoT multiplier, your DoT dmg will be multiplied by 1.35.

So DoT multiplier seems to be a good choice regardless of crit, as long as your main skill deals DoT dmg either by being a burning skill or by inflicting ignite.

[Ratt]

No, what's going on with DoT multipliers is that they're additive with one another but multiplicative with everything else, making fire DoT multiplier better than "increased burning damage" but worse than "more burning damage".

Let's pretend that Scorching Ray deals 200 damage per second per stack. Consider the following three collections of bonuses:

1. 50% increased fire damage, 50% increased spell damage, 15% increased burning damage, 25% increased burning damage. These are all just "increased" modifiers, so all the ones that apply to Scorching Ray add together. Scorching Ray is a fire spell that burns things, so all of them work. The final damage is 200 * (1 + 0.5 + 0.5 + 0.15 + 0.25) = 480 damage per second per stack.
   
2. 50% increased fire damage, 50% increased spell damage, 15% more burning damage, 25% more burning damage. This time, the burning damage modifiers are "more" instead of "increased", so each one is multiplied into the total after all the "increased" modifiers are applied. The final damage is (200 * (1 + 0.5 + 0.5)) * 1.15 * 1.25 = 575 damage per second per stack.
   
3. 50% increased fire damage, 50% increased spell damage, +15% to fire DoT multiplier, +25% to fire DoT multiplier. This time, we're using DoT multipliers instead, as are in the current game, so all the DoT multiplier sources add together, then the final DoT is multiplied by the DoT multiplier (hence the name). The final damage is (200 * (1 + 0.5 + 0.5)) * (1 + 0.15 + 0.25) = 560 damage per second per stack.

In short, having exactly one source of DoT multiplier makes it work exactly like a "more" modifier, and having several makes them gradually less effective than if they were all "more" modifiers, but they're still a lot better than "increased" modifiers. When all the burning damage got replaced by fire DoT multiplier stuff, they increased some of the numbers to compensate (like the Chieftain notable getting bumped from 15% more burning to +25% fire DoT), which is a net increase to people who didn't have lots of sources of more burning.

EDIT: Mindtroverted got it right in the post above, written while I was writing this.