In April I tried split ticketing for the first time and managed to get a low price from Portsmouth to Penrith. I was playing around on the split ticketing site yesterday and tried Portsmouth to Barnstaple, I managed to find prices ranging from £40 down to £20. The £20 price surprised me because that was early in the morning, the after 10.00hrs price was higher, even using my Senior Railcard.
Ticket splitting can make an amazing difference to price.
To take an example of a journey I often do...Chesterfield to Birmingham..it is nearly always much cheaper to buy a Chesterfield to Derby return, and a Derby to Birmingham return than a Chesterfield to Birmingham return.
All Chesterfield to Birmingham trains stop at Derby anyway so you can still catch exactly the same train. (NB Chesterfield sells Derby to Birmingham tickets, no need to buy them at Derby.)
The wheeze that is even stranger is buying tickets for destinations beyond where you are going. For example, Chesterfield to York can often be done by buying a ticket for places beyond York and just getting off at York, (Unless they have been put in recently, York has no ticket barriers,)
A good general tip is to go to local ticket office (when they are not busy!) and say “Can you tell me cheapest way to get to....” Most are very helpful..and know all the tricks.