Leadership training in Scotland is piecemeal and too often fails to give aspiring headteachers the right support to make the step up, according to the director of the country's main routes to headship.
Deirdre Torrance, programme director for the Scottish Qualification for Headship Unit at the University of Edinburgh, is calling for a national review of leadership preparation.
She argues there is scant research evidence to support certain approaches and that coaching programmes, which have gained popularity "at a remarkable pace", lack intellectual rigour.
School leadership, along with teacher quality, was identified in the Donaldson and McCormac reviews last year as one of the most crucial areas for the Scottish education system to address in the coming years.
But headteacher representatives and other leadership experts this week echoed Ms Torrance's concerns about the state of leadership training in Scotland.
"Across Scotland . we have the skill and capacity to identify and support aspiring heads. To date, we have not used that capacity to best effect," writes Ms Torrance in Policy and Practice in Education, in a recent edition focusing on coaching and mentoring.
The use of "coaching and mentoring" in teacher CPD is in itself a concern to Ms Torrance; she pinpoints a "lack of consensus as to the distinctiveness of coaching as compared with mentoring, or as to an agreed definition for coaching".
There are "dangers inherent when personal development is emphasised at the expense of intellectual development", she writes - a view also expressed in another chapter of the same journal by its co-editor, Christine Forde of the University of Glasgow.
"The place of scholarly activity to inform reflection on current and future practice cannot be overplayed," Ms Torrance says. "Without it, there is a danger of not moving beyond a cosy, comfortable and familiar frame of reference."
Programmes preparing teachers for headships are still an "act of faith", she writes. CPD for school leaders lacks cohesion, while there is "scant research" into coaching approaches.
She wants aspiring leaders to get experience of more than one programme before deciding which to choose, guided by a "national framework" encompassing a range of approaches.
Alex Wood, a former secondary headteacher who works at the Scottish Centre for Studies in School Administration, agreed "overwhelmingly" with the points made by Ms Torrance.
Leadership training was too "ad hoc", although he cautioned against going too far in the other direction so that training became overly- prescribed.
Ken Cunningham, general secretary of School Leaders Scotland, said that without a better national overview, there was a danger of leadership training being replicated around the country.
Aspiring leaders should get short-term experience in national bodies, such as the inspectorate, he added. Such opportunities were available, but it was "a bit haphazard".
The Scottish government was trying to address issues highlighted by Ms Torrance, he added.
`Policy and Practice in Education - Coaching and Mentoring' edited by Christine Forde, University of Glasgow, and Jim O'Brien, University of Edinburgh
A flavour of leadership training
National CPD team: now part of Education Scotland, it manages the Flexible Route to Headship, which emphasises coaching and mentoring, on behalf of the Scottish government.
Various universities: Edinburgh, Strathclyde, Stirling, Glasgow and Aberdeen provide routes to the Scottish Qualification for Headship, perceived as a more academic approach.
Scottish Centre for Studies in School Administration: has run leadership programmes for education professionals for more than 30 years.
School Leaders Scotland: offers a leadership programme that runs throughout the year, including tailor-made events for authorities and individuals.
Columba 1400: social enterprise and charity that works with people who can influence young people's lives.
Scottish Borders Council: its one-year Future Leaders Development Programme emphasises coaching.
South Ayrshire Council: its Leadership Development Programme aims to get teachers into promoted posts within three years of completion.