Enron guideline calculations (and a fascinating post-Booker question)

In this list of first-cut Enron sentencing questions, I speculated that the (advisory) federal guideline sentences for Ken Lay and Jeff Skilling could be life or at least 360 to life.  Confirming my instinct is guideline guru Frank Bowman, who already has prepared a snazzy PowerPoint presentation, entitled “Sentencing Ken Lay & Jeffrey Skilling” that you can access here thanks to Peter Lattman at the WSJ Law Blog.  Frank concludes that both Lay and Skilling face guideline recommendations of life sentences based on his calculations (which, notably, do not even include enhancements for obstruction of justice).

In thinking (and talking to others) about the Enron guideline calculations, one especially fascinating post-Booker question has my mind racing: Which version of the guidelines should apply to Lay and Skilling?

I am pretty sure the fraud guidelines were amended significantly to increase sentences in white-collar cases in November 2001 and again in November 2003.  Before Booker came along, it was settled law that ex post facto concerns generally required district judges to apply the version of the guidelines in place at the time of the crime.  (This old-world reality itself raises some issues, since arguably some offense conduct took place in late 2001.)

After Booker, there is a reasonable argument that ex post facto concerns no longer limit the application of the current guidelines even if they provide for harsher sentences.  (In fact, I believe Judge Easterbrook has some dicta in a post-Booker opinion to this effect.)  After all, the guidelines are no longer binding law, just intricate advice. 

Shouldn’t Judge Sim Lake at sentencing consider the most up-to-date advice from the Commission?  If the guidelines themselves are so darn reasonable and incorporate all the 3553(a) factors (as a few district judges and many circuit judges like to stress), why should Judge Lake rely on old, out-of-date and less reasonable advice from 2000 or 2001 when sentencing Lay and Skilling?  In short, many of the justifications for attentiveness to the guidelines in the post-Booker world seem to call for applying the latest version of the guidelines now that they are only advisory.

So, dear readers, should the 2000 guidelines or the 2001 guidelines or the 2005 guidelines apply to Lay and Skilling?  And what version of the guidelines will prosecutors to argue for (given than we can be sure the defense will argue for the most lenient 2000 guidelines to apply)?