Playing deviations % advantage?

[RoadWarrior]

Do playing deviations give you an extra % edge over the current 1-2% average edge that comes from counting, or are all the true count index playing deviations already factored into the 1-2% average edge someone gets from counting cards?

I remember that i believe Semyon Dukach has mentioned that it adds 15-20% somewhere but maybe i misunderstood it in the wrong context. 15-20% does seem a bit high and I'm wondering if hes applying that 15-20% to the additional 1-2% from counting.