There’s been some discussion about moving toward a relation-based model for railway infrastructure (as well as for train routes). This removes the need for each section of railway to be named as part of the GWML. In practice it doesn’t really matter much anyway. I always just tag the way with the name tag of the tunnel or bridge/viaduct etc.
Yes, that’s right which is partly why there’s some discussion about using relations to group infrastructure.
Routing isn’t really that useful on train tracks - you can’t walk along them, or drive along them for example. The only things that are routed along them are trains and train operators would know the names of the tunnels etc. The relation-based model would even solve it for that last group of users.
Are you on talk-transit?
Some really interesting discussions come up on that list from time to time.