One of the larger problems is that unless the creator includes the name of the route in the session name or at the very least includes the route name in the description it is a real pain downloading some session and discovering that it is also downloading some route I never heard of. If you confine yourself to only downloading TRS19 routes/sessions this is mitigated to some extent since there are so few 4.6 routes out there, wait until there are hundreds or until you decide to try some of the older routes.
I recently went through this with a session I found. I had hopes that it would be for one of the American routes I have but no, it was for a very nice English route that I didn't have and which also downloaded along with the session. I really didn't want another English route since I have my hands full with all the US routes I have but there it is, I suppose I'll run the session (since it is quite good) a few times and then delete both.
Edit: I have over 600 routes in TANE and only 126 in TRS19. Many of them are incremental development or experimental duplicate routes.
