George Zimmerman opts out of "stand your ground" hearing.

Why? His lawyer claims there's too much time pressure preparing for the jury trial, but there must be a better reason.

University of Florida law professor Bob Dekle [thinks it's likely] that [Zimmerman's lawyer] O'Mara doesn't want to go through a bench mini-trial and possibly tip off the prosecution about its strategy should the "stand your ground" plea fail.
"If you're not 100 percent sure you're going to win the 'stand your ground' hearing, you just end up telling the state what your defense is and you've got nothing with which to surprise the state at trial," says Professor Dekle. "What you want to do at trial is catch the state with their britches down."

Several new developments suggest that Zimmerman's defense attorneys are having some success finding information that could raise doubts among jurors about the state's version of events. For one, the defense has been digging furiously, with the judge's permission, into Trayvon's social media history, which may present a more complex, edgier picture of the youth.

Also on Tuesday, a key witness for the prosecution was caught in a second apparent lie amid probing by the defense. A woman who says she was on the phone with Trayvon as Zimmerman pursued him originally gave her age as 16, though she was really 18. And she also said she missed Trayvon's funeral because of a hospital stay, which wasn't true.

And here's Jeralynn Merritt, noting that at the "stand your ground" hearing, Zimmerman would have the burden of proof (by a preponderance of the evidence), but at the trial, the prosecution has the burden of proof beyond a reasonable doubt. Even though the defendant could lose at the "stand your ground" hearing and still go on to win at trial because of these different burdens, you can see why you might avoid the pre-trial hearing unless you were quite sure you'd win. And:

O'Mara can still file a motion to dismiss based on ["stand your ground"] immunity... at the close of the state's evidence and renew it at the close of his case, before it goes to the jury. The judge would determine the motion based on the evidence presented at trial. If denied, O'Mara can still argue self-defense, including self-defense based on the immunity/stand your ground statute, to the jury....

If the jury rejects self-defense, including that based on the immunity statute, Zimmerman can argue on appeal that the court erred in not dismissing the case based on the immunity statute before it went to the jury....

Much more at that second link.