tunnel test

so I just need to get this right.
anything that pokes through a tunnel is a hazard, thus fail?
Is that how it works?

[hyyyper]

Basically, yes.

However, there are certain cases where something poking through a tunnel is not a fail:

1. If a tunnel-to-tunnel collision occurs on a single block (between the lift and a brake run, for example).
2. If something is in the tunnel below the track, not hitting the wheel assembly.
3. Woodies have different tunnels, so you might want to change the track style to a steel one during tunnel-testing.

Some tunnel to tunnel intrusions are actually not such, as only the outer part of the tunnel (of which has thickness) intrudes, not the inner envelope. In addition, intrusions must occur with catwalks and the station in order for them to appear realistic. Anything that doesn't intrude the tunnel more than the catwalks/station are generally safe.

That said, a lot of tunnel testers (at least in the past) lack any basic common sense. A slight intrusion into the lower corner of the tunnel is safe if it doesn't stick in very far. (This is because the train's wheel assemblies aren't going to grow arms.) The entire track must be simultaneously tunneled for the test to be consistent.

My current avatar is satirical of those who make improper tunnel tests.