Three-ring circus ... err, three-way circuit split

I joked here a few weeks ago that the federal circuits' disparate handling of Booker "pipeline cases" was developing into a twelve-ring circus.  However, with the Seventh Circuit's work in Paladino and the Fifth Circuit's work in Mares, now "just" a three-way circuit split on plain error has become pretty clearly defined.  Updating my circuit review here from a few weeks ago, here's the simplified plain-error basics:

The "defendant must prove" plain error standard.  The 1st, 5th and 11th Circuits are applying the most rigorous plain error standard by requiring defendants to make a specific showing of prejudice from the application of mandatory guidelines (the reasonable probability of a different outcome) to satisfy the third step of plain-error review. 

The "let's ask when in doubt" plain error standard.  The 2nd and 7th Circuits have adopted the general rule that, whenever the impact of the guidelines being advisory is unclear, the Circuit will ask the sentencing judge whether a defendant was prejudiced by advisory guidelines so as to satisfy the third step of plain-error review.   

The "presumption of prejudice" plain error standard.  Though only clearly articulated in the 6th Circuit, it seems the 3rd, 4th, 6th, and 9th Circuit have all adopted a general presumption that a defendant was prejudiced by being sentencing pursuant to advisory guidelines so as to satisfy the third step of plain-error review.

Significantly, the government has sought en banc reconsideration of the plain error rules established by Hughes in the 4th Circuit and Ameline in the 9th Circuit.  But the rulings by the 2d, 5th and 7th Circuits (and maybe also the 3d Circuit) have all come through quasi-en banc collective decision-making procedures, so it appears that these circuit splits are firmly entrenched.  (It also remains to be seen where the 8th, 10th and DC Circuits will place themselves.  As detailed here, both the 8th and 10th Circuits have en banc oral arguments scheduled for this week.)

I have speculated previously here and here about whether the Supreme Court or any other institution will seek to clean up this plain error mess.  In a system purportedly designed to achieve a measure of sentencing uniformity, the plain error circuit splits — which may be a sign of other significant post-Booker circuit splits still to come — are certainly disconcerting.