Seventh Circuit upholds another large upward variance

Judge Posner yet again talks up district judge discretion after Booker through his opinion for the Seventh Circuit in US v. Johnson, No. 06-2156 (7th Cir. Dec. 13, 2006) (available here).  Apparently (though the opinion does not clearly state the guideline range) the defendant in Johnson was facing a guideline sentence of 12-18 months, but the district judge decided to impose a sentence of 77 months.  Clearly put off by the defendant's arguments on appeal, Judge Posner concludes the opinion affirming Johnson's sentence by stating that his "crimes would have justified on grounds of both retribution and deterrence an even longer sentence than he received. The statutory maximum of 108 months (9 years) would have been reasonable. The judge displayed lenity, not the reverse as Johnson argues."

On the facts, Judge Posner's opinion does not trouble me.  What does trouble me is that, after a case like Johnson, Judge Posner and others are still inclined to call the guidelines "presumptively reasonable."  If 108 months would have been reasonable for the criminal conduct in Johnson, why did the vaunted guidelines advise a sentence of only 12-18 months? 

If the district judge had imposed a sentence of only 12 months in Johnson, would Judge Posner have found that sentence reasonable had the government appealed?  Does reasonableness in a case like Johnson really extend from 1 to 9 years imprisoment?  If so, is post-Booker reasonableness review, which is supposedly to reduce disparities, any real substantive review at all?