I don't believe I have seen the issue discussed in an opinion before.
Well, on December 3rd, the Arizona Supreme Court issued State v. Price, Case No. CR-06-0435-PR. The majority opinion reverses a sentence because of Sixth Amendment problems created by Blakely's application to Arizona's sentencing system.
Justice Hurwitz wrote a concurrence in Price that addresses precisely this issue:
Price raised only Sixth Amendment arguments on appeal and the Court’s opinion thus appropriately turns only on the denial of a right to jury trial. But even when a jury trial is afforded, a serious Fourteenth Amendment due process problem is presented if the “catch-all” is the only factor that makes a defendant eligible for a sentence beyond the presumptive term.Slip op. at ¶¶26-29. (The Arizona Supreme Court numbers paragraphs, which has to be the future to accomodate web citation.) Because Price did not raise the 14th Amendment Due Process problem, Justice Hurwitz is "content to leave final resolution of this conundrum to another day."
. . . .
A defendant has no notice, in advance of the conduct that exposes him to jeopardy for the “aggravated crime,” of precisely what is proscribed under the critical “catch-all” element. It is as if the criminal code had one punishment for theft, and another for aggravated theft, the former consisting of theft simpliciter and the latter consisting of the elements of the theft plus “anything else the court or the state may someday later find relevant.”
Doug Berman calls the "conundrum" "another tough Blakely nut" in his post on Price. I don't think it is either a conundrum or a tough nut. It's just an issue that no one has raised. The focus has been entirely on Blakely's Sixth Amendment implications. Even Price didn't raise the issue in his appeal. And he obviously had at least one justice waiting to return serve.
With the April 2005 amendments to Indiana's sentencing statutes and their evisceration of Blakely in Indiana well behind now, one might think that this issue is of purely academic interest among Hoosiers. It's just possible, though, that the 14th amendment common law crime claims that were not raised in direct appeals would provide some fertile post-conviction ineffective assistance claims.
Thanks to Doug Berman's work and his Blakely in the States mashup on Sentencing Law & Policy for making it so easy to catch up and keep up.