If true, then the GOP ought to be able to get ~20% of the black vote if we do it right.
You're right! But "doing it right" requires that we not pander to the black vote and sponsor "black issues".
Instead, what it will require is being openly and honestly conservative. Promoting conservative principles to black audiences will do more to attract black votes than promising what Democrats promise. And, in the long run, will better benefit the black community -- along with the white community and the Latino community and the Asian community, etc....