Do you really need the SUB, MON and CON files ?

edit

Hello As I was learning about these files and how to write code with them, I started to ask myself if anyone else really uses them to do contingency analysis, I mean, you could write even more complicated code with the RAS Module. But as I learned so far, you need to create the DFAX and ACC files in order to add the RAS Module definitions to the contingency analysis, so its like you use these files as a nexus for the RAS Module to take care of the contingencies. My question is.. Should I focus in the SUB MON CON or in the RAS Module, or both ? And why ? Thanks for any insights