Well that's not how this law professor views it:
University of Miami law professor Tamara Lave said this change by O'Mara may be a signal that he thinks his case for self-defense is solid even without the special provisions afforded by "stand your ground."
Then isn't this poor defense by ZImmerman's lawyer? If there is an additional special provision why wouldn't you use it? Reason for a mistrial or appeal later in the process? Most likely appeal I doubt that a mistrial would be called for not using a possible defense.
Or does his lawyer know that following someone, getting out of your vehicle after the 911 dispatcher tells you to stop following and let the police handle it, and shooting them isn't really standing your ground. It is in fact potentially escalating the situation to a point where a gun is "needed" for self-defense?