The thing is, you go more often for a SE when you play Phi, so you actually have a lot of GPP to double. If you're Financial and cottage everywhere, with just one specialist here and there, running Pacifism won't change much. Then, if you have a food-rich map and can afford a lot of specialists and pop working the cottages, why not.I'm a little puzzled by your saying that you "always use it with a Phi leader, if not Phi then rarely." From a relative standpoint, it's not giving you as much of a boost if you're PHI (versus if you're not): 50% more GPP than you would have had anyway (if PHI) vs. 100% more GPP (if not). I'm not saying it's not worth using with PHI, but to me it seems more desirable for non-PHI leaders, not less. Same thing for the Parthenon--more beneficial from a relative standpoint for the non-PHI leader. Also, Pacifism benefits all cities with the state religion, and Parthenon benefits ALL cities, so the "Phi + Parthenon + NE in GP Farm" you mention, while it could be a powerhouse for one city, does not make use of the potential benefits of having multiple cities farm GPs. Can you say more about your approach--for example, do you always focus on just one GP-producing city?
If you're going for a single GP farm, building the National Epic here is enough, no need to run an empire-wide civic and frop the benefits of the others religious civics for a single city.