Teacher training is "in danger of collapse" unless schools and local authorities change their views about taking students.
Ministers have responded to the crisis in student placements by calling in the inspectorate to conduct an immediate study, but a similar investigation by researchers at Paisley University concludes that the "grace and favour" approach of schools will no longer do.
The study - presently at draft stage - covers schools, local authorities and university lecturers, and is led by Estelle Brisard in the university's school of education. It predicts that the system cannot survive much longer without intervention.
A last-minute panic has ensured places in schools for virtually all students this term but the pressure is repeated throughout the session and the spring term sees even greater strain in secondaries. Some 40 Glasgow University students complain this week that they are still waiting for places (Letters, page two).
Schools are even more reluctant to take students because of the pressure on them to raise attainment, the study into school-university partnerships in initial teacher education confirms.
One teacher admitted: "It is a burden on schools to place students appropriately, not damage the teaching that goes on in schools because we are all aware of exam results and we have to meet targets. So yes, it is a big burden."
Other tensions are said to include the loss of assistant principal and senior teacher posts and the consequent lack of designated staff to supervise students; the focus on the probationers' one-year induction scheme; and the feeling among teachers that schools do not get much out of the partnership with universities.
Even in highly committed schools, Mrs Brisard says, teachers acknowledge that taking students is time-consuming and involves complex bureaucracy, especially when more than one university is pressing for places. Some schools refuse to take students and others only two a year.
Many are unsure about their responsibilities. "I don't think anybody could force you to do it but there would be some pressure from our local authority to say, 'look, why are you not helping the next group of students?'," one said.
Another said: "There is no incentive to take a student. It is a lot of work but, from a professional point of view, I do feel that they need to come somewhere and it can be really nice if you are looking for someone eventually in a department, if someone is good."
Schools often see their main role as the education of children with the education and supervision of students as a secondary responsibility. It is up to university-based tutors to run the system, according to many teachers.
But university staff told the researchers that they are also under pressure, with tutorials being cut back and reductions in tutorial visits to schools being considered. The study points to "considerable tension" in the training system which staff feel could lead to a major breakdown.
One director said too much is expected of university teacher training.
"Everything is being put in there. There is behaviour management, enterprise, modern languages - everything - and things are being squeezed," he said. The only way to address this was by continuing professional development. It was impossible to deliver everything in a year.
Mrs Brisard suggests there is a desperate need for a different form of partnership which takes the roles and responsibilities of schools and local authorities more seriously. At present, there is an "almost total reliance" on the seven universities which run training to maintain standards and manage the system.
Any new approach will demand a national framework to ensure consistency across the country.