Bush has a career ERA of 4.65 now over 1035 IP. Other pitchers with an ERA in that same general range with 600+ IP include Marquis, Floyd, Silva, Chen, Suppan, Lohse, Perez, Francis, Jackson etc. Sure you don't build your rotation around them but not like Melvin is somehow an idiot for keeping a guy around that fits this mold. If you use xFIP instead taking into account he is in a bad park for his skillset and plays with a bad defense behind him he is a 4.45 xFIP pitcher. Other pitchers around the same xFIP include Willis, Padilla, Blanton, E. Santana, Davis, Garza, Meche, Arroyo, Carmona, Cain(yes outside of that park he would not be a 'stud'), Garland, Snell etc on top of many of those same names. Almost every team has 1 or 2 Dave Bush type pitchers in the rotation, usually one is a young up and comer and one is an older guy. Dave Bush is hardly a symbol of anything, he is just a #4 pitcher on a team that has struggled to produce #1-#3 quality arms.