The thing was, he was good in serious acting roles, I thought. He had a depressive and serious air about him that whenever he tried to perform comedy it just seemed so forced and not genuine.
Exactly.
His "comedy" routines reek of speed and cocaine. Nothing there is funny at all really. He does those annoying voices, one liners and looks like he is on the verge of collapsing at any minute. Its like that with all of his "comedy" routines.
His acting though, was always quite good in his serious roles. He did carry that that sadness with him and it worked.