I've noticed many ECS movements across the Strathclyde area and wondered why they aren't used as express services, albeit with odd stopping patterns but could still be useful.
For example, 5C05 1808 Carstairs to Yoker C.S. could run as 1C05 1808 Carstairs to Garscadden, stopping at Motherwell, Rutherglen, Argyle Street, Glasgow Central Low Level, Partick, Garscadden. Then operate as 5C05 1932 Garscadden to Yoker C.S.
[http://www.realtimetrains.co.uk/train/G80722/2019/04/01/advanced]
For example, 5C05 1808 Carstairs to Yoker C.S. could run as 1C05 1808 Carstairs to Garscadden, stopping at Motherwell, Rutherglen, Argyle Street, Glasgow Central Low Level, Partick, Garscadden. Then operate as 5C05 1932 Garscadden to Yoker C.S.
[http://www.realtimetrains.co.uk/train/G80722/2019/04/01/advanced]