Or take a journey that IS on the map. Wimbledon to Waterloo. The TfL journey planner gives the correct and sensible answer at an Oyster fare ...
The problem at the heart of these multiple anomalies is that the fares system is trying to squeeze together different businesses with their individual financial responsibilities plus a need (either real or aspirational) to show a profit!
Which challenges the whole philosophy of the "Tube" map.
Should it be an "Oystercard" map?
Should there be a concerted effort to create a unified network, unified fares and then a unified map?
Or are we stuck with confusion and complexity?
What about the "London Network" map showing Tube and Rail?
Or is the answer that it simply doesn't matter as most people are regular "commuters" and anomalies outside of home work travel simply do not bother people?
And fbb does realise that the Mayor (or Transport for London) would like to take over the whole of the former Network Southeast but the DaFT (Department for Transport) won't let them.
There are some challenging questions which will, sooner or later, need to be answered.
Tomorrow, another question. What IS an interchange?