O'Mara would open himself up to a malpractice suit if he didn't obtain an immunity hearing.
That said, I think he's been too deferential, especially at the start, and especially relating to the state's duty to produce evidence. He missed arguing the 15 day deadline that the state was under, where the 15 days starts on the day he files a motion agreeing to open-book discovery. He pushed that out a good month or two, when he should have been a thorn in Bernie's side.
Likewise, he didn't argue much when Zimmerman was illegally incarcerated.
And yet he's already busily making plans with the judge for the June party as if there will be no meaningful immunity hearing in April.