One thing SWR lacks severely is speed. Surprisingly GTL UBL stertch has zero SFs fastest is 18047 Amaravati averaging mere 55 kph and that too on paper in reality always adds minimum 60 minutes delay after HPT. Buses are faster than trains on many SWR routes. Track doubling should definitely be a boon for SWR as well as the passengers. Really travelling through SWR sucks at times.
PS: 2847/48 Amaravati was the first SF to connect UBL and GTL but sadly SWR failed to run it on schedule so it got degraded to 18047/48. I'm still hoping that one day it is back to its SF avatar.