Songwriting
Dream Theater has long been known for its group writing process, so it is sometimes difficult to identify which member of the band authored a particular song or song section (although, on some DVD commentaries, the band members have identified certain parts as, e.g., "a John Myung riff"). With respect to lyrics, Myung wrote the lyrics to one song per album from Images and Words to Metropolis Pt. 2: Scenes from a Memory; after this Myung did not contribute any lyrics until A Dramatic Turn of Events. Mike Portnoy once commented in a chat session that this is probably because Myung's lyrics usually needed some work by the rest of the band to fit to the song. As a result, the band eventually imposed an unwritten lyric rule that required lyrics to be "properly formed, phrased, constructed, etc. to go with the melodies," and, "since then, John has kind of backed off."
Read more about this topic: John Myung