Would this be because of the poor history of serious accidents on the Glasgow electric suburban services, all from passing signals at danger.
There were major fatal collisions at Shields Jc (1973), Paisley (1979), Bellgrove (1989) and then Newton (1991). It did seem a surprising sequence of them.
To which might be added the fatal collision at Pollokshields East Junction on 11 June 1974. This, along with the Paisley and Bellgrove collisions involved 'ding ding and away'. Both Pollokshields and Paisley had involved conventional double junctions There was a strong belief within ScotRail (rightly or wrongly) that driver only operation under the Strathclyde Manning Agreement would greatly reduce the likelihood of starting against a red. (Shields was a running line collision that might have occurred anywhere before TPWS.)
I am not aware of any other serious incident involving a conflicting move that was initiated by a DOO train starting from a station against a red.
Thanks for and have read it am sure you would agree that Lanark and Motherwell via Bellshill services effectively stopped calling at Newton how was it that the Sunday Motherwell to Balloch via Bellshill still did so and only stopped doing so in the wake of the Newton rail crash?
This was because services on Sundays were hourly on each route rather than half hourly. The only reason that the PTE was willing to fund the East Connecting Line and its connections was to enable Bellshill services to still serve Newton in those sort of circumstances, engineering works, etc..