I can see why they have the warning. I don't think it has much to do with RP. A more experienced player will have a better idea of which imms are more active during their playing time. This will make it much easier to be able to contact you god. Newbies also might get frustrated at spending 50 or so hours trying to contact their god with no reply and decide that CF sucks without giving the other classes a try. You don't have to be elite to be an empowered character, if you are lucky enough to pick a god who has the same playing time as you, your first character could be empowered.