I honestly couldn't disagree more with this statement. I have no idea who you think Jack Nicholson is, but he is not a raving maniac or a murderer.
To me Jack did everything right in his performance (okay, there's a few things I'd change). He has a wild and scary look in his eyes that makes him look crazed an unpredictable, yet very intelligent. His constant laughter was great. You actually feel like he finds his murders funny... and yet he still has a sort of charisma that makes you believe that other men would follow his crazy schemes.
His make-up and costume are great. They are the Joker. His skin is bleached, his hair is green and he's got an insane grin that believe it or not, your common movie goer still has no idea how it was done.
While I agree with your comments about the makeup and wardrobe, never once have I watched the movie and thought Nicholson's Joker was "wild and scary", "unpredictable", or menacing in any way (except for his post-transformation confrontation scene with Carl Grissom, and the potential menace ends immmediately after he delivers the "Wait 'til they get a load of me" line).
In all fairness, I don't blame Nicholson at all. I recall seeing a promotional interview with Michael Keaton (prior to the release of the film) in which he mentioned Nicholson would often approach him after a scene and ask about his (Nicholson's) performance. According to Keaton, Nicholson was having difficulty gauging his performance because he wasn't sure whether or not his facial expressions and emotions were showing properly through the Joker makeup. Keaton said his response was usually something to the effect of, "Are you kidding? You're Jack Nicholson! It was great!"
This told me two things. First, Jack Nicholson is a consummate professional who, even with all of his successes in his acting career and the accolades he'd received at that point, was very willing to accept constructive criticism and/or suggestions on how he might improve his performance. Second, there weren't many people involved in the production who were willing or able to offer the constructive criticism and/or suggestions he was asking for. And, realistically, I can understand this. After all, with the exception of supporting cast members like Jack Palance, Pat Hingle, and Michael Gough, Nicholson was the "big dog" on set--how do you tell a seasoned veteran that his performance isn't quite up to par when you're still trying to make a name for yourself in the industry (which both Keaton and Burton were doing at that point)?
That said, I also agree with your subsequent post that there really is no "definitive" way to portray any fictional character (I'm paraphrasing to convey my point, of course); everyone has their own interpretation of who and/or what the character really is and, as such, it would be impossible for a single performance to satisfy every fan. But, for me anyway, the exchange of thoughts, opinions, and ideas on the matter is what makes it fun!
