It doesn't really matter to Zimmerman's case, and we can't answer that without talking to Martin.
FYI, we've been over that multiple times on this thread - both people can be guilty of a crime. The victims reaction only has to be a foreseeable consequence, not a legally justified or sensible one, to give the shooter a problem.
See, here's where I'm gonna *really* disagree with you. If Martin's actions were not legally justifiable (i.e. he was not in REASONABLE fear of death or serious bodily injury) then *his* attack on Zimmerman is sufficiently disproportionate to Zimmerman's actions (whether he was following or chasing) that Zimmerman becomes once again justified in using deadly physical force to defend himself (since he *did* have a reasonable fear of death or serious injury).
Florida Law deals *specifically* with this scenario:
776.041 Use of force by aggressor.—
The justification described in the preceding sections of this chapter is not available to a person who:
(1) Is attempting to commit, committing, or escaping after the commission of, a forcible felony; or
(2) Initially provokes the use of force against himself or herself, unless:
(a) Such force is so great that the person reasonably believes that he or she is in imminent danger of death or great bodily harm and that he or she has exhausted every reasonable means to escape such danger other than the use of force which is likely to cause death or great bodily harm to the assailant; or
(b) In good faith, the person withdraws from physical contact with the assailant and indicates clearly to the assailant that he or she desires to withdraw and terminate the use of force, but the assailant continues or resumes the use of force.
776.041 (2)(a) deals *EXACTLY* with the scenario you are describing. Even if Zimmerman "provoked" the confrontation by following (or chasing) Martin, Martin's response was disproportionate to the situation. Let me line it right up here:
The justification described in the preceding sections of this chapter is not available to a person who: (2) Initially provokes the use of force against himself or herself, unless: (a) Such force is so great that the person reasonably believes that he or she is in imminent danger of death or great bodily harm and that he or she has exhausted every reasonable means to escape such danger other than the use of force which is likely to cause death or great bodily harm to the assailant; or (b) In good faith, the person withdraws from physical contact with the assailant and indicates clearly to the assailant that he or she desires to withdraw and terminate the use of force, but the assailant continues or resumes the use of force.
So unless Zimmerman was "attempting to commit, committing, or escaping after the commission of, a forcible felony; " I would imagine that barring other evidence coming forward that Zimmerman shot Martin unprovoked, this case is heading towards dismissal or acquittal.