Cowboys masquerading as plumbers

Now - I'm not really blaming the plumber. After all, he has a qualification which says he can do the job. He probably thinks he is qualified and he is - in some respects. He can pass exams, he can fit and repair and inspect modern central heating systems.
The problem is that most of us don't have all-singing, all-dancing modern condensing combination boiler systems.
I have an old-fashioned back boiler which heats up to ten radiators and a primatic hot water cylinder.
So an experienced plumber would have taken one look at my cylinder and sussed it out as primatic. Not so the so-called qualified plumber who came to sort out my central heating. He was surprised, not to say confused, that there was no secondary cold water supply tank for the central heating. He looked at the hot water cylinder and stated that it was all wrong and where was the cold water supply coming from for the central heating part of the system. He took his new toy, a power flushing appliance to my heating system. It blasted out lots of nasty, black gooey sludge. This was probably the only positive thing he did. When he re-started the system he seemed surprised that no hot water got through to the radiators. At this point he was still unaware that it was a primatic system.
He set the boiler on its highest setting, opened all the radiator valves and hoped. When very little heat got through to the radiators he expressed surprise, mild annoyance but mainly mystification that it hadn't worked. He then stated that he could not explain and said "Try it for a bit and give me a ring later on, I'm off to watch the Rugby on the TV."
I called him the next day when there was no improvement. He finally came round and that was when he discovered that the cylinder was primatic.
Now I am not an expert but primatic cylinders need a completely different treatment to direct cylinders. The fact that he had not sussed the type of system immediately shows that college learning and City and Guilds qualifications are no substitute for years of experience. With the best will in the world this guy has set himself up as a plumber. He probably even believes he can do the job.
There is nothing better than training on the job with an experienced qualified tradesman. You can learn all the wrinkles that the theorists in the colleges don't even know about let alone teach! Once he had got his paper qualification, our friend should then have gone as a practical trainee with a real plumber to learn about the real world of pipes and heating and joints which don't necessarily occur in the theoretical world of college education.
I wish the guy well in his career. But he can rest assured that he will not get a penny out of me for the "work" he has done on my heating system.
I do not want to be used as a learning curve for a theoretical plumber.
Should he kick up about lack of payment I will post his name, address and telephone number on this site and others so that all the people in my local area will not be caught in his delusion of qualification.
Perhaps it is the job of these colleges to train cowboys . . .
Perhaps I might even give him a Stetson . . . .