Oh, I've never heard about that before.
Yeah, whenever he's worked under a major studio the constraints have proven to be too much for him. Again, he's able to meet their demands and "Cop Out" for example he was able to pull in under budget but he's made it clear how anti-Hollywood he is and how he prefers to work on his
own material on his own schedule.
I think he's also expressed that he's pretty much "retired" from movie making. It
is a shame though because I think he could certainly do a JLA script but, at the same time, his "talents" as a director -with all due respect to him- are limited and may not suit a big-budget action movie.
But if anyone in the "Geek community" could pull off a decent story he probably could. His Batman books were good and, honestly, his Superman Lives! script isn't
too bad, again, considering the constraints and requirements put on him.