How does Instilled Doubt work?

Classes Priest
1

Question - Which one of these is how Instilled Doubt works?

I have 20% critical strike. I take 2 points in Instilled Doubt.

  1. Now my Shadow Word: Pain, and Vampiric Touch DoTs have a 35% (20% + 15%) chance to crit every time they trigger.

  2. Now my Shadow Word: Pain, and Vampiric Touch DoTs have have a 23% (20 x .15 + 20%) critical strike.

I was hoping it was #1, but it feels like #2.
Just wanting to clarify.

2

I’m pretty sure it’s option #1, as some class talents specifically state “you gain x% more critical strike from critical strike sources” like Serrated Blades for hunters which would be the appropriate wording for option #2

Otherwise unless you stack crit it would be a completely useless talent. I am also curious though if anyone has a definitive answer.