His reforming moment came at a celebratory ceilidh he had arranged at New Lanark heritage village on the eve of his school, Williamwood High in East Renfrewshire, hosting a week of theatre sessions as part of a two-year Workshop Europe project that had already taken a group of pupils and teachers to Dresden, Warsaw and Prague.
These workshops are part of the Young Euro Theatre Laboratory scheme, aimed at promoting positive ideas on European citizenship. For the project, schools in the four participating countries are partnered with a local theatre company. In Dresden, this is the Theater Junge Generation, the largest young people's theatre company in Germany. Williamwood High's partner is the Collusion Theatre, which works regularly with schools in East Renfrewshire.
Over the two years, the schools have been taking it in turns to host a week's residency, in which the pupils explore the realities and possibilities of European citizenship. Each time, the results have been recorded, to be fed into the final performance of the project in Dresden in August.
"Everywhere else, the four nationalities worked separately, but at New Lanark we mixed them up," says Mr Mackenzie. "It certainly made for some very impromptu communication. Some of their English was as good as our Czech or Polish!"
There is no doubt in his mind that the project has been very worthwhile.
"It has been really fantastic for me to see how the children in this school have developed their self-confidence through drama," he says.
"We only got into this because we haven't got a drama teacher. When pupils want to do drama, we have to send them to sister schools.
"We saw this scheme, apart from its other obvious merits, as a way to ease us into drama. After the summer we are moving into a splendid new school - quite possibly the most modern in the UK if not Europe - where we shall have two drama spaces and possibly two drama teachers."
Much of the project organisation was down to Susanne Wallace, who will pick up an award as one of East Renfrewshire's 10 Teachers of Excellence at the end of this session.
For Collusion Theatre, the project has furthered both its work in East Renfrewshire education and its presence abroad, which already includes Ireland, the Netherlands and Lithuania.