Whether factual error is categorically immune from plain error review?

QUESTIONS PRESENTED I. Whether factual error is categorically immune from plain error review? IL. Whether sentences arising under Guideline 2G2.2 tend to produce substantively unreasonable sentences in the ordinary case? Whether a court of appeals may evaluate the empirical foundation of a Sentencing Guideline, or policy critiques of the Guideline, in order to determine whether the sentences it produces are reasonable in the ordinary case? il PARTIES Robert Dion Ables is the petitioner; he was the defendant-appellant below. The United States of America is the respondent; it was the plaintiff-appellee below. ill