[Talk-GB] Unsuitable for motors etc.

[SomeoneElse]

Has anyone got any bright ideas about how best to map "Unsuitable for 
Motors" etc. signs?  As I understand it they're not really access 
restrictions, just advisory.  Currently they tend to be mapped as notes 
or as "motorcar=unsuitable" (which I'm yet to be convinced about because 
that's an access tag):

http://wiki.openstreetmap.org/wiki/Road_signs_in_the_United_Kingdom
http://taginfo.openstreetmap.org/search?q=unsuitable#values

Using a "note" is fine for recording the information but the fact that 
it's not in a separate tag makes life difficult for renderers and 
routers (I'm thinking something along the lines of the Australian 
4wd_only=yes).  Anyone got any thoughts?

Cheers,
Andy