Hmm, I see what you mean. The fare-check rule applies when selecting a routing point for an origin and/or destination station that has more than one available. You don't need to apply the fare-check rule when the origin and destination stations are themselves routing points, or where a station has only one routing point available.

So, anyone game to actually try this? By my reckoning it looks like you could use this loophole for cheap travel to Bristol, Hereford, Newport, Gloucester, Cheltenham Spa, and others using an off-peak London-Oxford ticket. Just be prepared to carry a copy of the appropriate sections of the NRG and argue your case to the ticket collector

There must be many other similar loopholes around the network?