If SWR really wants to utilise GDG-SUR line, first they should complete and inaugurate Harihar-Harapanahalli-Hospet line. Then, many trains can divert via that line and go via GDG-SUR line. 2 loco reversals at UBL and GDG can also be avoided, apart from distance reduction. But, it will skip UBL and so SWR will not be ready to do this. It is not clear why GDG-SUR is taken up for doubling.