Of course you can, only I don't have ts12, so I can only tell you how it's done in ts2010.
In principle when you create a route in the first screen where you have to name it and choose a region you immediately fill in a name for the session to use as base as well. All further editing on the route you do via the session menu for that route where you choose the before named base session. This way you allways keep industry settings and whatever else is kept in the same base session file. Do remember that when you actually want to work on the route itself you need to change to a route layer if you open a route session combo this way.
Other sessions you can all 'derive' from this base session by adding stuf and saving it under a different meaningfull name.
In ts2010 this is easy to do, I presume ts12 won't be any different. :hehe:
Greetings from dusk Amsterdam,
Jan