Championship fell races are never navigation events. Navigation skills are necessary for safety. Map and compass are still mandatory for a good reason. If a fell race is also a nav event eg mountain marathons, HPM and similar then the RO usually states no GPS.
Just about impossible to police and to be honest. There’s little difference between that and someone who reccies the route to death. If anything, it reduces footfall from that point of view. There are safety advantages for those in trouble who may be assisted off the hill by one or be able to accurately pinpoint where they are.
This was debated in the FRA last year. I have no plans to limit GPS for the reasons above but do have to say, that I think nobody is going to run to their potential speed.whilst looking at their watch. It won’t make a champion out of anyone. Championship races are like a precession of sheep anyway. It’s a race and the fastes round the course wins with or without GPS.
I do understand your concern Nick but it’s just not enforceable.