Sometimes growls can add to a song but yeah, they're becoming overused, most of the melodeath bands I like are the ones that incorporate clean vocals as well.. Amon Amarth are dangerous as fuck but does not hold a candle Scar Symmetry...
The clean really takes the song to a new plane in my opinion, if it were just growls it wouldn't be anything special.
EDIT: Mr Bungle... where's your avatar of the cow... I liked that better.
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