GPS shouldn't be used as a primary means of navigation anyway, so its irrelevant.
Furthermore, GPS shouldn't be used as the primary means of navigation in non certified aircraft
AAAARRRRGGGGHHHHHH 
(as well as being totally wrong as any kind of a summary of the legal position)
The problem is that obviously from the posts on PPrune many people in the UK don't understand GPS and its capabilities or limitations so it is very hard to get proper training to use it properly.
How true.