Ah thanks for that – ok, I had assumed that NR and Underground fares were the same if they covered the same zones, but they’re clearly not! I guess my calculation would have been right if I had used purely Underground from London Bridge to Richmond, as the extension fares are cheaper and below the cost of the through ticket (£4.30)
Out of interest, is there a published list of extension ticket prices, as it all seems to be a black box of mystery, and not available on the TfL website?
And next time I’ll remember to do paper tickets for the evening peak on NR, as that’s cheaper with Gold Card in this case – should’ve read your article first!
Thanks again Mike