[Talk-GB] inferred single-carriageway NSL?

[Dave F.]

Hi

You've probably seen the numerous edits by chriscf. Can anyone explain 
the purpose of these edits & what the the tags below even mean?
I've had no reply to an email sent to him a couple of days ago

In my locality, each of his edits already had a maxspeed (with units) 
tag accurately mapped by people on the ground. I don't understand what 
these extra tags add to the OSM's quality

I'm most concerned about the 'inferred' references, which, to me, is no 
better than guessing; something that should not be a part of OSM.

Comment:     units in speed limts, add/remove special road status, 
attempt to infer NSL status

Tags:
FIXME:nsl = inferred single-carriageway NSL - remove this tag once verified
source:maxspeed = UK:nsl_single

Cheers
Dave F.