Isn't that asking for trouble? If an eastbound train is just a couple of minutes late, it's going to delay the westbound service, and whereas the eastbound is simply heading for Scarborough to terminate, the westbound has to be as close as possible to path to get sensibly through the busy York, Leeds, and Manchester areas.
I think the timetable changes in May are going to be a disaster for the Scarborough line, to list a few problems from the latest timetable I have seen:
1. Apart from early mornings no direct trains to Man Pic, so a lot of journeys that are currently 1 change at Piccadilly will take probably at least 20 mins longer, probably more like 30 mins (to name a few journeys that I do regularly, Stockport, Chester, Warrington, Preston...)
2. Timetabling at Malton will make service even more unreliable
3. Connections at Seamer to Filey and points south will almost always result in 55 minute wait, as the new northern hourly service is times to leave Seamer at the same time as the train from York arrives, and the train from York is nearly always a few minutes late.
4. Commute time journeys to York in the morning now 06:42 then 07:38 from Scarborough (OK so earlier train at 06:00, but thats not going to help York/Leeds commuters)
People in Hull are already unhappy at the changes (Look North earlier in the week, MP was complaining that service will be worse) I think people in Scarborough are going to be of the same mind. I'm expecting the A64 to get even busier in a morning.