The strategy to boost research in a new London medical school could also benefit undergraduate teaching, given "vision and great managerial expertise", according to Peter Richards, dean of St Mary's Hospital medical school.
St Mary's has been a part of Imperial College since 1988 and plans are underway for mergers with parts of the Royal Postgraduate medical school, Charing Cross and Westminster medical school, and the National Heart and Lung Institute.
Professor Richards, giving the Aleck Bourne lecture at St Mary's, said that research and postgraduate education went hand and hand, and opportunities improved the larger the centre of expertise, its clinical experience and its interactive team.
But he questioned how far a large school was good for undergraduate teaching.
"On the face of it, to be large is cost effective; at least it would be if the students were taught in vast groups in aircraft hangars," he said.
"However, if the General Medical Council has its way, whole group lectures are largely an approach of the past.
"Small group tutorial teaching and self-directed learning are the order of the day and probably of the next century."
Cost-effectiveness depended on achieving a greater range of expertise within each academic discipline, not in being able to teach more students with relatively fewer staff, he warned.
"The new Imperial College school of medicine will not save academic money, but it does hold out a real prospect that the investment will be more effectively used both in education and research."
Professor Richards predicted "formidable" difficulties in shifting students and staff between the college's basic medical sciences and clinical sites, and suggested that interactive technology might be the solution.
But he stressed that scientific excellence must extend beyond the physical, mathematical and biological sciences, which were about "the discovery of the hard and the fast and relationships between them". He added that behavioural sciences needed to be substantially strengthened.