The "point to point" journey point is a good one, though. In other words, journey time should be measured from the time you set off from your start to the time you reach your destination. I met up with some people who live in Glastonbury today. Their friends drive to Castle Cary and then take the train to Paddington if they have a London appointment, whereas they take Berry's Superfast coach -
http://www.berryscoaches.co.uk/timetables-fares-london-superfast . They recon by the time they drive to Castle Cary and pay to park there and then take the train ("from Castle Cary they stop everywhere") and have to get on the tube at Paddington, it's just as fast and much cheaper to get on the coach that's five minutes walk from their home and transfer to the tube at Hammersmith.
