It depends on the training centre of course. My local college insist you must be a practicing electrician with a 2330 or equivalent and regs qualification; it's almost as if they're trying to put people off signing up! On the course every 3rd week is practical, which obviously helps prepare students for the practical exam.
These cowboy training centres just seem to be about taking your money and leaving you to get on with it - when they go selling courses to people with no experience and little previous training then stuff them full of information but still no practical experience it's little wonder most of them fail, ÂŁ600 or so worse off.
As the training centres are well aware, there's no regulatory body to stop them doing this, but if anyone asks I'm happy to give them the reality.