So basically, you should only take Faith if you have the AB (Miracles) (i.e. (There is an exception for weird science, where a mad scientist could give you his device.but I've never seen that happen anyways).
If you do not have the arcane background, you will never roll the skill, which makes it a wasted investment. These skills are really just for arcane backgrounds (AB). So, there are a few skills in the Test Drive Rules that are marked with an asterisk. Oh, I knew there was another reason I brought up the alternate edges thing.
*This is an addendum to the response to ashersky's character build.but it's important for everyone.*