Navigational Skills must surely be adequate for the race in question.

This particular route is the Edale Skyline. Bits of it can be very complex in mist - as folk have found out in the past.

If your skills aren't up to it then you cannot fulfil the organisers requirements, and you should not enter.

It's this wishy washy "I'll be alright if I get behind someone in a local pennine vest" kind of mentality which forces the poor organiser to insist on things like mobies.