I'm still struggling to see the point of any of this - it seems to be going beyond the usual "solution to a problem that doesn't exist" to "not a solution, or a problem, and even if it was a solution then it still wouldn't work because of other issues -i.e. the passing loops". Barnstaple has a regular basicallly clockface (?) hourly service, that is about right for the line, that fully utilises all of the current infrastructure very efficiently. As far as I can tell this would be an awful lot of work, would only be useful to allow excursion trains for which there is probably no market for, and which would be unable to run between the service trains because all of the passing loops are used. If there was a desire to make Barnstaple half-hourly, then I could see the point of installing more loops, and making the Exeter - Newton St Cyres section double track rather than 2x single track to make that work, but even then, a single platform at Barnstaple would surely be adequate.