He said this before that he just don't do them that often anymore really. It's like on the new album, they had to change Enter Tragedy's song structure because it was the same old ''fast aggressive In Flames song'' that they've done so many times before, and he said that those things are getting boring since they've already done it so much. But actually most of the times when he growls live, he growls parts that are actually in the album, but the high pitched scream is much higher volume than the growl in the layer, for example the ''these thoughts'' part in Take This Life, the death growl underneath the scream is barely audible, but it's there.
Yeah, I understand him being bored by doing the same stuff. Just sucks because I really rate Anders' screaming and growling, whereas in comparison I'm not a big fan of his singing.