Subtlety Rogue Nightstalker Tooltip is incorrect

I apologize this is my first post. I was simulating my Subtlety rogue Elyyinnâ-Sargeras (alt code 0226) and realized that the tool tip for Nightstalker is incorrect. In game the tool tip displays “While Stealth or Shadow Dance is active, you move 20% faster and your abilities deal 12% more damage.” Meanwhile the tool tip AskMrRobot uses says 88% instead of 12% increased damage I don’t know if this affects how the simulator works but it if the simulator uses the tool tip that’s a wide margin of error.

The simulator uses 12%, not sure what is up with the tooltip.