Up to 1965 that included 2 separate Sheffield stations, and that determined routes.
Ex Midland trains, from/to Sheffield Midland, ran via the Midland route: Rotherham Masboro, Cudworth, Normanton to Altofts Junction. Trains to/from York and beyond then went via Castleford.
Ex Great Central trains, from/to Sheffield Victoria ran via the Swinton and Knottingley route: Rotherham Central, Bolton on Dearne and Pontefract Baghill.
The two York routes converged at Burton Salmon.
Well I've just dug out the NER summer 1958 timetable. Things you do when it's too hot to venture out. Looking at southbound MF departures from York we have the following-
0730 all stations to Sheffield Midland via Pontefract
0920 Newcastle to Bristol via Sheffield Midland. Calling at Pontefract
1000 Newcastle to Cardiff via Sheffield Midland. Calling at Pontefract
1023 Newcastle to Bournemouth. Called at Sheffield Victoria but also Pontefr.act.
1148 All stations to Sheffield Midland via Pontefract
1226 York to Banbury. Called at Pontefract and Sheffield Victoria
1248 York to Bristol. Called at Sheffield Midland and Pontefract
1418 FO York to Gloucester. Called at Sheffield Midland
1423 Newcastle to Bristol. Called Sheffield Midland and Pontefract.
1615 All stations to Sheffield Midland via Pontefract
1700 FO Fast to Sheffield Midland
1716 Newcastle to Birmingham. Called Sheffield Midland and Pontefract
1840 York to Swindon. Called at Sheffield Victoria
1915 All stations to Sheffield Midland via Pontefract
2106FO Newcastle to Birmingham . Called Sheffield Midland and Pontefract
2130 Newcastle to Bristol. Called Sheffield Midland and Pontefract
2222 York to Swindon. Called Sheffield Victoria and Pontefract
The trains for the GC route ran via Sheffield Victoria as stated.
However, given that practically all the others called at Pontefract, it is clearly wrong to say they ran via Cudworth