I am an admirer of Charles Rennie Mackintosh's work - at least before the pints of heavy took their toll.
There was a time when every CRM building was interpreted as a step along the way to the magic kingdom of the Modern Movement. The 1952 work on CRM by Thomas Howarth was titled Charles Rennie Mackintosh and the Modern Movement (coincidentally, both Howarth and the author of your piece, Kenneth Powell, said that he accepted the job at 78 Derngate with 'alacrity'). Powell suggests that the rear elevation of Derngate is approaching Modernism, but I feel it is more of a design confusion than a confident CRM concept and is not an example of Mackintosh at his peak.
It is unfortunate that no photographs of the building before, or during, the work were shown. These would have enabled us to see how much was restoration and how much was recreation.
Northampton is no doubt proud of a CRM memento, but was such a rebuilding/reincarnation justified? Does the profession want to appear so elitist that it considers £1.5 million a 'modest budget'? I'm glad you don't find copies of the AJ in GP's waiting rooms - such a comment would not generate much positive PR for architects.
Nicholas J Blake, Canterbury, Kent