Are long appellate opinions a good or bad thing?

I like them, especially compared to the one word PCA that we see.

 But Judge Edmondson isn't convinced, writing this in a concurrence to a 104 page Judge Carnes opinion:

I stand with Judge Carnes about the correct judgment in this appeal: AFFIRM the District Court’s judgment to deny habeas corpus relief to the state prisoner petitioner.  I -- very respectfully -- do not join in Judge Carnes’s erudite opinion.  I stress that it is not because the opinion says something that I am sure is wrong or I am sure is even likely wrong.  I agree with much of the opinion, at least.  But the opinion says a lot and says more than I think is absolutely needed.
In my experience, longish opinions always present a strong possibility of error lurking somewhere in the text. That the opinion writer is a skilled and careful judge does not eliminate the risk. Furthermore, no one wishes to join in an opinion that they do not understand fully. It is hard, time-consuming, painstaking work for the panel's other judges to check long opinions, line by line, cited case by cited case. (Of course, always other cases are awaiting decision and also demand the judges' time and attention.)
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It seems to me that the incidence of long opinions has been on the rise in the last decade or, at least, more are coming across my desk. I should say that I, broadly speaking, do not agree that the length of an opinion necessarily reflects the thought, labor, and care that has been invested by judges in their endeavor to decide the case correctly. The shorter opinions often reflect the greater study and thought leading up to the ultimate decision. Mark Twain touched on a related idea: "If you want me to give you a two-hour presentation, I am ready today. If you want only a five-minute speech, it will take me two weeks to prepare."

Here's an article about the underlying case, in which Judge Barkett dissented:

The federal appeals court has upheld a death sentence against man who killed a sheriff’s deputy, even though the condemned inmate’s lead lawyer drank a quart of vodka every day during trial.
The 11th U.S. Circuit Court of Appeals in Atlanta, in a 2-1 decision issued Thursday, said that even though Robert Wayne Holsey’s trial lawyers did not do a competent job, their deficient performance did not prejudice the outcome of the trial. Holsey sits on Georgia’s death row for fatally shooting Baldwin County Deputy Will Robinson after an armed robbery of a convenience store in December 1995.
Holsey’s appellate lawyers noted that his lead trial lawyer, Andrew Prince, drank a quart of vodka every night of Holsey’s trial because he was about to be sued and prosecuted for stealing client funds. During Holsey’s appeal, Prince testified that he “probably shouldn’t have been allowed to represent anybody” because of his condition.
In its ruling, the 11th Circuit said the key question was not whether Holsey’s lawyers were ineffective. It was whether their deficient performance prejudiced the outcome to the point there was a reasonable probability Holsey would not have been sentenced to death.
Judge Ed Carnes, writing the majority opinion, said the abundant aggravating factors — such as the fact Holsey killed a deputy to avoid arrest and had a prior armed robbery conviction — outweighed any additional mitigation evidence Holsey’s lawyers could have presented to the jury had they been doing their job.
Judge J.L. Edmondson concurred with the decision, but he indicated it was a close call as to whether the poor performance of Holsey’s lawyers prejudiced the outcome of the trial.
In dissent, Judge Rosemary Barkett said the jury never learned that Holsey was subjected to abuse so severe, frequent and notorious that his neighbors called his childhood home “the torture chamber.” Holsey’s mother beat him with an extension cord, shoes and a broom and would hold his head under the bathtub faucet, Barkett wrote, also citing testimony that the house was infested with roaches and reeked of urine and rotting food.
Had the jury heard more about Holsey’s “horrific child abuse,” Barkett wrote, there is a substantial probability he would not have been sentenced to death.