Some people only consider the inland side to be the Fife Circle, as the coastal side is the Edinburgh-Dundee line. But I suspect
@lachlan is talking more about the services. Previously most of the local trains did the whole circle in one direction or the other, whereas now the inland side is served by Edinburgh-Leven shuttles. Try looking for a train that goes directly between Kirkcaldy and Glenrothes, I think there might be one a day now.
The reason for that split was precisely because demand for one side to the other was found to be minimal, bordering on non-existent. It was useful for diagramming when there wasn't anywhere to send them at the other end, as it meant you could run right round without changing ends. Now, with 2tph to Leven, one each way, there is unfortunately little demand for a full circle service, as it's a better use of capacity to just send them to Leven and back.
This simply highlights the lack of capacity to the East of Waverley.
Time to get those tunnels re-bored and get relief lines.
Indeed
With Glasgow-Alloa journeys timetabled in just 44 minutes, 55 minutes does seem a remarkably long time to travel the 18 miles from Alloa to Dunfermline. When steam specials operated on the line, how long did they take?
55 minutes along a 30-35mph max line, with three stops (Kincardine, Clackmannan and Valleyfield for Culross) seems about right. With substantial line speed increases you could get it down to about 35 or so minutes, but that's not fast enough to run an hourly service on one unit in steam rules, so you'd need proper signalling and a passing loop, and if you're building a passing loop then you need a couple extra minutes pathing time to make sure they meet in the middle, so let's call it forty at a push.
That's an hour and a half, give or take, from Dunfermline to Glasgow. Currently, you can do it via Haymarket in an hour and fifteen, depending on how good the connection is. And that's only for Dunfermline, for most of the rest of Fife, Haymarket will always be quicker.
Thing is, 1tpd isn't enough to realistically evaluate demand.
No it's not, but we also have excellent data for the number of people changing at Haymarket and number of tickets bought, good data for buses and reasonable data by counting the number of people going from Fife down the motorway to Glasgow using ANPR.