Anyway, having posted all the links - some queries/thoughts which have always bugged me...
[*]There is not, to the best of my knowledge, any guidance on the use of bend signs and chevrons. This leads to huge inconsistencies across the country with some almost non-existent bends having huge chevrons and some hairpin bends having no warning. I therefore always ignore bend warning signs as unreliable.
I haven't got it on this PC, but try 'PR494 Bend Treatments on the A377 between Cowley and Bishops Tawton - Final Report' by TRL, also 'Hazard Warning Signs and Markings on Bends on Single Carriageway Trunk Roads' by the Scottish Executive.
[*]There is not, to the best of my knowledge, any good guidance on the use of warning signs for things like accompanied horses or bikes. This again leads to discrepancies in their use - largely depending upon the environment you are in. I know there are Horse Warning signs in Exeter for very few horses, yet in North Somerset there are many horses and no signs (to name 2 places I know well)
[*]There is a whole schedule of directional type signs, these seem to cover every eventuality except the one you want to sign...
[*]There is not, to the best of my knowledge, any good guidance on the use of Brown Tourist Signs. This often leads to huge arguments between (for example) the HA and the Local Council.
There's DMRB, Volume 8, TA93/04, TD52/04 and TA94/04. Having said that, their criteria seem to go out of the window the moment the HA come under pressure from business owners/political lobbying.
I think Signs is a Huge Topic, one which is a whole new headache for anyone trying to keep it up to date.