The text is helpful but it also fudges things:

Item 2 reads:

(2) For the purposes of paragraph (1), a reasonable excuse includes the need—

The word "includes" must make things very difficult from an enforcement perspective.

Through the British Horse Society, we know that additional reasons include the need to care for a horse in DIY livery.

Paul
Costock, UK
2014 4/4 Rolls Royce Garnet Red
Disco 5
Teddy - 17h1 Irish Draught cross