The point about this, however, is that it is a change for local flows, ones where there generally aren't period returns in any case. It does seem likely that this fare structure will have to be implemented to advance both RDG and government policy for PAYG to essentially be how local travel works. If the single fare from Westbury to Ashchurch is set at the price of half the day return, people making a period return will see a reduction in fares.How is it simpler? Buy a return ticket, come back on any train (or any train after a certain time etc) on any day within a month.
vs, Buy a ticket and have specify what day you want to return for the other ticket. Lose massive amounts of the flexibility you had, and many of the rights you had as a passenger for a given ticket price.
For what it is worth, I don't like the way this is going because there are opportunities to use the flexibility that the current fare structures offer, particularly to travel to more than one place, but the reality is that the majority of the railway's passengers are simply interested in travelling point to point, and are seen to have really taken to PAYG-type structures in London without any real complaint.
I suspect we will see a range of these local area PAYG schemes without overlaps and then a different structure for longer distance travel.