Not being affiliated with a PhD program isn't a problem in itself. Review is often double blind, and frankly I don't think most people care much about your credentials. However, it is very difficult to publish in many areas with out "speaking the language" the way the natives do. If you are an outsider to the area, this is a big disadvantage. (Not eliminated at all if you have a PhD in a different area!) For better or for worse, you will be more successful if you try to fit with the style of the journal, and cite everything in sight.
