Bking:
Yes last Adr "course " I went on really taught the rookies about the reality of blowing a tank,about the problems of blowing a gas tank too fast,about the most important things if your going to run a tank.
All I can say is that the course has to meet the standards set down in the syllabus, so you can argue all you like with the DfT about the rights and wrongs of the syllabus because the syllabus comes from the DfT.
As with anything else, we all have an opinion though. 
Bking:
And you know why? because the nearest these “experts” have been to a tank is a picture on a computer.
Oh really?
If you knew anything at all about the requirements, you wouldn’t have written that. 
I see that you haven’t lost the ability to spout more hot air than you claim to have heard on your course.

Bking:
But these"experts" bought themselves a bit of paper that qualifies them to “teach” you (at a price) to be allowed to do a job these shysters know jack [zb] about.
Now there you go again, a seemingly inexhaustible supply of yet more hot air from the master. 
Apart from the piece of paper that you’re only partly correct about, there are other criteria that an ADR instructor has to meet before they get approved by SQA.
1.) They have to be ex-industry, including tanker experience if they are applying to teach the tanks module.
2.) They have to be able to demonstrate an adequate knowledge of the ADR Regs.
Now for the part where I might agree with you… (did I write that?) … I’ve heard that some ADR instructors have been known to flesh out parts of the course that they’re weak on by inventing some stories. In my experience, I’d say that’s mostly to do with the tanker module and it’ll be because seasoned instructors believe the tanks module to be a bit longer than needed. However, as I said earlier, we have to follow the syllabus as set by the DfT. Sorry, but that’s the way of it.
The basic requirements (from the DfT) for an ADR tanks module are:
1.) A minimum of 10 X 45mins training units. (Lessons.)
2.) There must be at least one overnight break in a tanks module. (In other words, it cannot be completed in one day.)