A line was going to be built in the late 1930's(Dawlish Avoiding Line)..All that is needed is a bit of track that goes straight from Exeter to Newton Abbot, it's only that bit at Dawlish that is a problem.
A few years ago,a patient from Langdon Secure(!) Unit,just outside Dawlish walked to Truro(it took him a week)..What was bizzare about the episode was that he was not missed....It was his family who raised the alarm when he turned up on the door step..!!Not from my house it's not! Have walked from Teignmouth before but it's a stretch.