If you are competent then Guides are not required, if you are not competent then step away. ....
So any electrician with the on-site guide.
Any electrician who refers to any of the available guidance notes (gn3, 8, whatever).
Should they step away?
Guides are a very useful resource, yes they can be misused, but overall I would prefer that we end up with more consistency in reports and overall installations via having them available and used wisely