Responding to the latest funding row between councils and the 18-strong group, Mr Dean said: "I do think the culture of blame that runs through society could well give these schools a break and recognise their strengths. The human condition will govern what they are allowed to achieve.
"There is some immensely strong and diverse practice which wants encouraging, not castigating. The schools have moved aeons in the past 20 years from the situation where they were punitive and containing establishments. We have all sorts of checks and balances now."
Mr Dean was founder and head of Raddery for 17 years before becoming a consultant in residential work and a visiting professor in Russia. He helped establish the special schools group following an earlier battle with the local authorities that buy places. Around 600 pupils currently attend.
Councils complain that rising charges over successive years have been way above inflation rates at a time when their own budgets are being slashed. Equally vehemently, the schools deny that costs are out of line. An average placement can cost pound;30,000 a year and some more than pound;60,000.
Education and social work officials and child protection agencies are also questioning whether children benefit from the system and are now favouring local provision. The Kent report on the care of children living away from home has highlighted concerns.
Mr Dean, however, believes councils will have to rely on the independents for the small number of pupils with problems at home and school and says there will always be a role for specialist schools where the degree of disturbance works against the accepted wisdom of educating and caring for children in their communities.
"The authorities want to have a service which they can account for much more easily. But it may not address the psychological needs of the youngsters. A lot of kids can be helped locally but it is a question of choosing the right resource for the right kid."
Referring to the funding row, Mr Dean said: "The fees for any residential treatment programme are horrendously expensive but what is the alternative? It may be more cost-effective to spend money in the short term."
The cost of non-intervention with young people had to be set against the alternative cost to society. Mr Dean said many problems would continue into adulthood without appropriate therapy.
Part of the problem is a lack of research. "The attempts that have been made have all been flawed because of the immense difficulties in coming up with a research programme that was meaningful. It would be good if someone could change that situation."
The nagging public concern about incidents of abuse in residential settings is never far removed from schools' priorities. As Mr Dean said: "It's not a case of if you get an allegation, but when."
There are fine lines and guidelines about appropriate behaviour but disturbed children have to realise someone cares for them, Mr Dean points out. Sometimes a hug can help.
The sector is facing its difficulties, not least over funding and the impact of the Children Act with its higher standards of inspection, service and performance. Some schools could well follow Lendrick Muir, near Kinross, and go to the wall. For Mr Dean, there is a job to be done. Needs remain. "No one's in this for an easy life," he says.