> What you describe are the operational rules and interlocking.
> Operational rules are difficult to map in a project as OpenStreetMap
> which has a strong On The Ground Rule (i.e. things need to be verifiable
> on the ground). One can see equipment on the track (balises, magnets,
> contacts etc.) but the detailed operation rules are not reflected by
> signs (e.g. a board with something like "Company A Rulebook ends here").

It seems to me that in regards to mapping train protection/train
control/operating rules, that we have several considerations going for us:

- There may be no physical infrastructure to an operating rule, but
there is consistent behavior.  Consistent behavior can be observed,
physically.

- It is appropriate to map speed limits on roads.  While these are
generally accompanied by speed limit signs, legally (at least in the
United States) it is not the sign that governs, it is the legal status
of the limit.  If protesters remove or change the signs, the legal speed
limit does not change.  Thus when mapping operating rules, the "legal"
status of the tracks is what governs, not the presence of
infrastructure.  If some vandal removed the signal, train crews are
still required to stop for it.

- legal operating rules also matter for roadways that are public or
private.  They should be mapped differently to avoid confusion even
though there may be no physical infrastructure to distinguish them.

- This is information which would be useful to the community (including
myself, personally) and would not interfere with any existing features. 
It is the kind of information that already appears on other maps and has
for at least a hundred years (I have such maps in my collection).  Seems
to me that the default should be to favor usefulness.

Christopher Parker