Actually CNB-FBD-KSJ-MTJ route is not for ndls bound trains it's for the trains going to mumbai,adi,agra or you can say from kasganj your train can go to bareilly/izn and towards bhojipura but for NDLS it will again join the mainline viz Shikohabad and Bareilly already SKB(NCR) is overloaded with freights and normal trains and same goes for Bareilly(NR) packed with freights and normal trains.. and btw FBD-SKB route is one of the worst route with train's clocking 60kmph in normal season.. that too single line.. i guess that would be bad idea to divert passenger trains if possible diverting freights could help such that CNB-SKB section would become free from load of freights if they are bound for beyond skb..