under which following the guidelines would result in a sentence sufficiently unreasonable to trigger a violation of section 3553(a) is a context-specific question that I would decline to address in detail at this time, when our accreted stock of concrete examples consists only of a few eases of early impression. I would therefore decline to lay down any overarching principles today, except to note that the set of cases in which departures are required is obviously a narrow subset of the narrow set of cases in which they are even permitted. The question whether section 3553(a) requires departure in some particular case seems to me a question of law, on which we owe no particular deference to the district court’s conclusion. Cf. United States v. Ryan, 866 F.2d 604, 610 (3d Cir.1989) (<HOLDING>). However, to the extent that the district
holding that the question whether section 3553b permits departure in some particular case is subject to plenary review holding that claimed errors of law are subject to plenary review holding that whether a vessel is subject to jurisdiction under section 955a is a question of fact holding that whether a statute affects sentencing is a question of law subject to de novo review holding that a district courts determination of its jurisdiction to resentence a defendant is subject to plenary review