[hackinthebochs]

>I said one AAVE speaker would not be able to point out the grammatical errors of another.

Would you be able to point out the grammatical errors in standard english without having been taught standard english grammar all through school, while at the same time having it re-enforced through writing assignments, literature, etc? I don't know about you, but I very likely would not. The point is we don't have a built in mechanism to flag subtle grammar errors (although we can certainly tell if something "sounds" wrong, but this is likely through re-enforcement).