The power of separation of powers?

Judge J. Harvie Wilkinson's concurrence in the Fourth Circuit's Hammoud ruling provides a fascinating "separation of powers" arguments for why Blakely does not apply to the federal guidelines. Though I will need to re-read Judge Wilkinson's rich opinion to appreciate all it is saying, I think I have the basic logic: (1) the judiciary made the federal guidelines, (2) reading Blakely to require proof of guideline factors to a jury beyond a reasonable doubt converts these factors into de facto elements of new crimes, (3) but only the legislature can properly create and define crimes.

This is interesting logic, though it raises almost as many questions as the majority opinion in Hammoud (discussed here). First, though the US Sentencing Commission is nominally in the judicial branch, I have highlighted before that the USSC both in design and in operation is far more like, in Justice Scalia's words, a "junior-varsity Congress" than just a group of judges making sentencing standards for themselves. Second, given that the courts have consistently and widely held that the Ex Post Facto Clause applies to changes in the guidelines (see SG Brief at 25), haven't the courts already concluded that the guidelines do create de facto elements of new crimes?

Finally, I think there is a "through the looking glass" quality to this separation of powers argument, especially given the Framers' apparent interests in democratic checks and balances and in safeguarding individual rights through the Bill of Rights. The implication of Judge Wilkinson's argument, as I understand it, is that if and when Congress creates binding sentencing laws though traditional legislative means (securing approval by both houses and signature by the President), then defendants have the benefits of full constitutional procedural rights during the enforcement of those laws. But if and when a legislature finds a way to writing binding sentencing laws through a non-legislative means (e.g., creating an agency whose rules will be legally binding despite never being traditionally enacted), then defendants have fewer procedural rights in the enforcement of those laws. Whatever one thinks of structural constitutional arguments, I doubt the Framers (or Justice Scalia) ultimately imagined that defendants would get less procedural rights in the application of those laws that are created in less democratically accountable ways.