Witholding knowledge doesn't help anyone, nor does it protect jobs/livelihoods. If soemone asks a question on here or in the real world and I am able to answer I will. I have nothing to hide or fear. The problem comes when people get an answer which they don't like.
I could give the bloke next door detailed instructions on how to change his own CU. Anyone with reasonable hand skills and a basic knowledge of engineering/physics should cope without a problem. However, I would tell him that he can't without the test gear and knowledge to use it. He also can't because it needs to be notified and he isn't with a scheme. I also can't give him the knowledge and experience to find and sort any issues which may arise before, during or after. He may do it anyway and die or be injured. Stuff happens, move on.
If he asked about how something works, or what this that or the other does, or how to carry out a simple like for like swap I'd tell him. I wouldn't get all precious about him not having served a twenty year apprenticeship and cried tears of blood so that he could enter the hallowed profession of electrician.
