Having got just over a hundred pages in by the time I got back to Oxford last night, I found that Dawkins mentions the source of this suggestion, but of course the name escapes me at the moment.

I saw at Feltham that Stagecoach are doing MegaTrains too, these days, which would make the Reading-Feltham leg significantly more feasible.

(You may correctly deduce from this posting that I now have a working DSL again.)