In reality GB, its hard to say "how many times" you go over the glass and frames, it comes down to experience and confidence in you work.
If i am behind and trying to catch up, then i might not even touch the frames on maintenance cleans, and you can get away with barely scrubbing the glass, because over 4 weeks there wont be much build up of dirt, and the lightest going over with a brush will loosen the dirt, meaning that the most important part of the clean is the rinse.