Hey! You’re using logic! No fair!
No fair to whom? Some of the "Traybots" claim that Zimmerman's going to walk because the prosecutors are throwing the case. I don't think there's any way that the facts of the case support a conviction, and I suspect 99% of those claiming the prosecutor's throwing the case have no clue as to what it should be doing, but from an objective standpoint I nonetheless think that the "Traybots" are correct in claiming that the prosecutor is doing a far less effective job of handling the case than a competent prosecutor should be able to do.
Suppose that the prosecutor had called only those witnesses necessary to prove the points mentioned above. In the absence of any evidence to show self-defense, those points would on the face of it be sufficient to prove second-degree murder. Of course, the prosecution couldn't stop the defense from calling its own witnesses for the purpose of showing self-defense, but its questioning would be subject to the rules of direct examination, rather than cross-examination. Further, if the prosecutor's goal was to show that Zimmerman's statements at various points in the process weren't 100% consistent, it could do so in the rebuttal phase.