To recap: The Daily News said Roxanne Shante forced her record label to pay for her Ph.D. Slate refuted both her record label’s involvement and the Ph.D., period. Now, the indomitable Jeff Chang refutes Slate’s refutation, or at least calls out author Ben Sheffner’s strong music-industry ties and possible motives. Opening line: “If a rapper claims to be a killer, no one cares. If she says she has an education, they send in an investigative reporter, or at least someone who purports to be.” Shazam. Is Slate just fecklessly dabbling in “gotcha journalism”? “Too bad this couldn’t be settled with battle rhymes,” Chang concludes. It’s not too late.