There are three things everyone thinks they know about the new diplomas: that they are unpopular, the general public does not understand them, and they have a "schizophrenic" balance between vocational and academic learning.
Those last words belong to Professor Adrian Smith, a senior government adviser, referring to plans for a new science diploma. His was just one voice in a chorus of disapproval after it was revealed that only 12,000 students began diploma courses in September, instead of the expected 50,000.
Some are warning that this bad start must not be allowed to define the reputation of the qualification or it could face elimination, as happened to earlier efforts to bring vocational education to under-16s, such as GNVQs.
Andy Powell, chief executive of the Edge Foundation, said: "There are all sorts of challenges and issues with diplomas, and there are all sorts of aspects that need improving. What must happen is that the Government must see this as a process of continuous improvement.
"We don't want to see a review of diplomas in 18 months' time saying there are some really good things and a lot of things that are wrong, then the faults are exaggerated and we decide to get rid of diplomas and start all over again.
"Anything outside the traditional academic route of A-levels and GCSEs has been seen as the playground of policy-makers."
The Government has been defensive about the numbers beginning diplomas, saying that despite seeing its predictions dashed, it had always envisaged a slow start for the qualification. That may be rationalisation after the fact, but colleges are sympathetic to the view.
Kingston Maurward College, in Dorchester, Dorset, just missed its first- year target of 20 students on the construction diploma courses after last- minute drop-outs by the only two girls to sign up: one decided it was not for her, and the other one was understandably reluctant to be the only girl among a group of 14-year-old boys.
Despite that setback, the college now has a waiting list for diplomas next year, and is recruiting from the top-performing comprehensive school in the county, Thomas Hardye School, in Dorchester.
So what makes the difference between a "schizophrenic" course no one understands and one that has students queuing to join?
Kingston Maurward College has some natural advantages: a beautiful rural setting on the site of an 18th-century manor house, surrounded by creatures of all kinds tended by its animal care students, and with formal gardens beautifully manicured by those on its landscape courses.
Among this historic charm is a new Pounds 1 million building: a dedicated workshop for the construction diploma students. This massive investment was mostly funded by the Learning and Skills Council.
Eventually, it is expected that 60 students at a time will be able to use the plumbing, bricklaying and carpentry facilities.
The college says the maths that students use in calculating tolerances on pipe fittings or working out how to cut wood for fencing is, for many, a better way of learning.
Matt Old, head of the diploma centre, said parents and teachers have noticed a change in attitude from teenagers who were engaged in practical work and treated in a more adult way in college. "From 14 to 16, they do a lot of growing up. We have had a lot of comments from parents about how it's making a real difference to them," he said. "We treat them like little adults and that's what works. We give them the respect that they're not quite used to."
Colleges have called for greater involvement in the diplomas if they are to be genuinely practical courses, since they have the necessary facilities and teaching experience. According to the Association of Colleges, about half of diploma consortia are led by colleges, although they would like to see this figure increase. In the case of Kingston Maurward College, it will be taking the lead on its environment and land- based diploma, due to start next year, because of its specialist expertise.
"The practical or workshop-based experience is so central," said Maggie Scott, the AoC's assistant chief executive and director of policy. "It's about putting the needs of the young people first, rather than thinking that we can do this in Portakabins in the playground."
The Dorset construction diploma goes one better than providing students with two days a week in a working environment, bending pipes or laying bricks. When the students return to their schools for their remaining GCSE studies, they find that English, maths or science courses have been adapted to refer to the construction work they have done out of school.
As Jack Guilfoyle, 14, said: "At school, you think it's boring. But now when you're in science, they talk about building and it's more interesting. You don't realise you're learning stuff."
Crucial in the relationship between schools and colleges is the advice students receive.
Ms Scott said: "There is a recognition of the expertise in colleges, but this information, advice and guidance is still a big issue. In some parts of the country, colleges are invited to come into schools and talk to parents and tell young people about the benefits - to have taster days to show what kinds of things they can do."
Dorset schools have a long-standing positive relationship with Kingston Maurward College, having regularly invited the college to explain options to their pupils.
David Humphreys, academy head for schools at the college, said an early start was vital. "We're not saying it's a 14 to 19 agenda; it's from 13 upwards. Year 9 is when they make their options choices. We have to engage them before then," he said.
He said parents and students were less concerned about whether the qualification had credibility in the eyes of the educational establishment, and more interested in whether the teenagers would be interested in the day-to-day work of the course.
However, he said the equivalence to academic qualifications, with two days at college studying construction replacing two GCSEs, provided vital reassurance.
"That made the difference at parents' evening. They could relate to that," he said.
Good relationships between schools and colleges needed to be supported by the local authority, he said. At Kingston Maurward College, staff are effusive about the work of the county council. Its market research was extremely helpful, they said, steering them away from offering a retail diploma that probably would have proved unpopular.
One aspect that requires the most co-ordination is transport. The Commons transport select committee this week said more should have been done to ease the movement of thousands of pupils between schools and colleges, although it admitted there was no "magic bullet" solution.
Staff at Kingston Maurward College estimate that some diploma students might have to travel 35 miles to get to the college. But once again, it has a head start: because of its rural seclusion and specialist courses, it has run its own free bus services for many years, which now diploma students can use.
The arrangement is unlikely to be feasible for all institutions: the Association of Colleges is instead calling for free travel passes for all teenagers so that they can use local transport without fear of the cost.
Support from employers was also seen as crucial. A Pounds 10 million construction project in the heart of Dorchester - rebuilding the town centre around the former Eldridge Pope brewery site - has adopted Kingston Maurward diploma students, allowing them to follow the construction and learn from workers at all levels, including its architects and planners.
Some of this was attributable to the investment in the college's facilities: the workshops and equipment provided a clear signal of the programme's relevance to industry.
Students at Kingston Maurward seem unfazed by taking a new, untested qualification, but several have parents who worked in construction and were aware of the diploma. So enthusiasm for the qualification had spread by word of mouth rather than through national publicity.
"It's good to be first," Jack said. "It's nice to think you're starting something off. It's something that's going to go on for years."