Here are some basic diagrams of the St J and LV worked into the same trackage that the Conn River line also occupies.  There is a way to short circuit the shared trackage but it is not worth the disruption/destruction that would be necessary for minimal benefit.  Besides....the trains are interacting with each other more intensely with the shared arrangement.  It's a profitable compromise.

A through G represents the St J and LV.  There is room for more towns to be added per time and interest.  The diagrams are hopefully self explanatory.,  Will send out pictures when possible.