Tally Hall remains an eclectic songwriting team because they have four primary songwriters that tend to write their songs on their own and bring them to the band to work on and enhance.  They try to keep a good balance and equal share of songs by each songwriter on their albums.
The writer of each song was consistently written on the back cover of every album/EP until Good & Evil. The Tally Hallmanac is now the best place to find this information. http://www.hiddeninthesand.com/wiki/