Truth be told, George Clooney's acting was not the cause of the crapfest that was Batman & Robin in my opinion . In fact , it was the only thing grounded in the whole mess. When you have a director who says ; " they don't call them Tragic Books, they call them Comic Books". It was a sure sign that that Joel Shumacher had no clue what Batman was really all about. After the movie tanked Schumacher begged for another chance to do a dark version of Batman, he and Akiva Goldsman , and a slew of producers who knew better let it get out of hand.
They created this travesty that kept Batman out of the theaters for 7 years and almost killed the franchise. It must be a real blow to the ego of Schumacher to see what he did. George Clooney survived because he is a good actor and he could have been in a much better Batman film, had the other powers that be let him.