To me, these heroes with their great abilities had other options, setting aside the Phantom Zone or indeed the vagaries of prison rape by Light's fellow convicts.
Green Lantern had previously used his ring to put ablock in Major Disaster's head toprevent him from revealing his secret ID. (It drove MD somewhat nutty as depicted in GL #190 or thereabouts, but GL wasn't to know that at the time).
No need to wipe his brain: just put a mental block in it preventing him from talking about it. If GL couldn't do it, Zatanna could. Or whistle up Martian Manhunter to do something with his telepathy.
Or jail Light in a jurisdiction where no one speaks English, or where there are no supervillains to use the information Light could give them. The offence was committed in orbital space, not in the US. Take the fucker to Mozambique for trial, JLA, and let him talk about it to his heart's content.
Batman's anger had a point. Afflicting a captured felon with magical brain surgery is not exactly standing for truth justice and liberty. And zapping Bats was entirely unforgiveable.
Setting aside the OMAC Project, I'm kind of looking forward to Batman confronting that group. I think Deathstroke's efforts might be kind in comparison to what Batman might do, especially to Zatanna.
