Wisely, he has chosen not to chase too many hares. The IPA, he says, will be energetic in its defence of commercial freedom of speech, but will rally behind the Advertising Association's call for the industry to speak with one voice.
Nor will it try to shape the digital future, but confine itself to helping member agencies to master it.
Instead, MacLennan presents a stripped-down, but highly pragmatic, agenda. And it's hard to argue with that.
As he rightly implies, the industry's desire to be loved is unlikely ever to be returned by the world at large. Advertising's high profile makes it a perpetual scapegoat for the ills of society, and that is never going to change.
But if love will always elude the business, is it too much to expect that it should be given respect for what it does?
The way of achieving such respect is neither radical nor new. For some years, the IPA has been trying to convince companies of advertising's key role in their future health.
Yet the fact remains that the industry is misunderstood in far too many boardrooms. A lot more has to be done to make companies and shareholders understand more about the intangible assets that agencies create.
Effectiveness awards have a role to play in this, but clients who participate probably need no convincing. A lot of preaching is in danger of being wasted on the converted. In the end, the industry will be judged less by its rhetoric and more by how well it conducts itself.
The big question is whether or not, in undergoing what has been a painful reinvention of itself, the industry can kill off any lingering client perceptions once and for all. If MacLennan can help speed that process along, then it will be a significant achievement.