Memory plays funny tricks [the older I get the better I was] but does not the good Rool Book have a preface [ours did] to the thrust that:
The spirit and intention of these orders is to take precedence over narrow adherence to the letter of the law?
And each section began with: the purpose of this instruction is .......
Hence, for example, I used the Red Dragon Pullman [from Cardif]f and the White Rose [from Leeds] services, 1st class, with car parking included, breakfast on the train inluded, dinner on the return included, and half day subsistence, all because it was cheaper than whatever the current rules said [my faithfull admin king discovered this pleasant way of saving Her Majesty a few bob]. I cannot for the life of me think what the official method entailed: a coach and four and overnight in town, perhaps?