[Tagging] Does disused:railway=* require railway=disused?

[Warin]

On 7/28/2016 4:54 PM, David Marchal wrote:
> Hello, there.
>
> I've been told in a JOSM ticket (https://josm.openstreetmap.de/ticket/12866#comment:2) that the wiki states that disused:railway=* requires railway=disused, and, indeed, the wiki says that (https://wiki.openstreetmap.org/wiki/Key:disused:railway). I don't understand why as, AFAIK, the lifecycle prefixing doesn't requires this, as it merely intends to suppress the(highway|railway|*)=disused tagging. Requiring to keep this deprecated and redundant data sounds inconsistent and confusing to me, especially if this requirement is limited to railways. How do things stand regarding this matter?
>

My understanding is;

The primary tag is railway=disused.

Then you have a 'sub tag' to describe what is disused .. a railway station, light rail line etc.

That help?