...and when you "opt out" you forfit any favoritisim you may have received at your parole hearing."
According to the state of florida, when you "opt out" you get transfered to a non faith based institution and go thru the regular channels.
But I think you have a point here. Parole boards are full of stodgy self rightous assholes they probably would favor someone who was in a "faith based" institution, and what this amounts to is coersion by the state to profess religiosity.
It is a constitutionally forbidden practice. However, so is much that the government does these days.