jimmys69
MOODerator
I suppose my comment pre-supposed that all the songs were as loud as they could get without falling apart. When mastering a single, you can do what ever you want, but generally people will make it as loud as it can be without sounding like crap. Some songs have the potential to be louder than others simply because of the instrumentation and arrangement, other songs will never get that loud without being destroyed. You would have to match the one that can't go any farther, since you can always make something quieter without any sonic compromise.
Good answer!