There usually is a ground rod at each pole, certainly any pole with a transformer on it. I find little difference electrically between the service drops and a feeder to a separate building. I suspect that is why 230 and 225 have so much similar language. The only significant difference is the lack of overcurrent protection of service conductors and that really doesn't affect the point and method of grounding that much IMHO, only the grounding conductor size (250.66 vs 250.122).
From a lightning and surge standpoint, separating the neutral and ground at a remote site is troublesome. The only way to "stabilize the voltage to earth" is via your TVSS equipment and that will have a significant "let through" voltage before it triggers.
