If GZ fails to convince a judge at the Dennis Hearing that he more than likely acted in self-defense, his trial strategy will be revealed to the prosecution. Since it is an affirmative defense, he may also have to take the stand at the hearing, always a risky gambit; but I'm not sure on that point. Cboldt should have more info on that.
And since he has statements and videos to present as evidence, would he really have to take the stand in a SYG hearing???