Plane Sailing said:
But on 100% of the hits that you achieve, you gain +3.5 bonus damage. Since the chance to hit and the chance to confirm the critical are the same, I wonder if they two terms would cancel out once the maths is done...
If you think about it some more though, I'm actually *deflating* it with 10d6. As you say, a critical hit normally occurs on less than 10% of your attacks with the sword. If you roll a threat and confirm on 50% of the confirm rolls, you have a 5% total chance of scoring a crit... thus you need 70(!) damage to match the +3.5 average!!!
Let's get this thread back on topic.
This all depends on threat range and damage multiplier.
Examples:
1) Scythe with 40% chance to hit, 5% chance to threat, and damage multiplier x4.
This does +3.5 damage 40% of the time.
It does +16.5 damage 2% of the time (or 0.825 extra damage on average per successful hit)
2) Keen Scythe with 40% chance to hit, 10% chance to threat, and damage multiplier x4.
This does +3.5 damage 40% of the time.
It does +16.5 damage 4% of the time (or 1.65 extra damage on average per successful hit)
3) Longsword with 40% chance to hit, 10% chance to threat, and damage multiplier x2.
This does +3.5 damage 40% of the time.
It does +5.5 damage 4% of the time (or 0.55 extra damage on average per successful hit)
4) Keen Longsword with 40% chance to hit, 20% chance to threat, and damage multiplier x2.
This does +3.5 damage 40% of the time.
It does +5.5 damage 8% of the time (or 1.1 extra damage on average per successful hit)
As can be seen, none of these examples show that the extra burst damage is that worthwhile. And Keen does not help the average Burst damage that much either (although Keen helps the other normal damage a lot).
The Flaming portion does (in these examples) 4 to 7 times as much damage (without Keen) as the Burst portion. So, upping it to 10D6 is actually enflating, not deflating it.
So, what does Burst really give you?
It stacks with the normal energy portion of the weapon to allow some energy damage to get through in cases of Resist Energy 5 or Resist Energy 10 situations.
And, it boosts damage a little bit on a critical.
That's not that big of a deal.