Saying exactly that !!!
I have worked on many new builds where guys dont have any gas experience what so ever and yet are installing boilers and hobs .
i worked with a guy that never had any gas experience at all yet had a u gauge and would test to what he thought was the method of a tt.
I worked for a large company ( no names) a few years ago that had a guy on site installing boilkers and hobs and was only third year apprentice . Like i said have worked all over and yes this goes on at a rather large scale.
have seen it too