Er if you can see the ground thru a gap how big does that gap have to be (judt wondered as turned dack the other day due to lack of gap)
I've never come across any reference, or details of any enforcement, on this.
I guess the reason why the UK CAA imposes this additional requirement (additional to an ICAO PPL) is that UK pilots are not taught to navigate using methods other than dead reckoning.
It's all a bit silly since you can be in clear conditions but in poor vis e.g. 3000m which is still UK PPL legal but you can't do DR in 3k vis. Well, instructors can but that's because they know the area
