Ganley insisted on answering virtually every question – what ever it was – with a populist let-the-people decide tinge while Cohn-Bendit struggled to get his point across and through facial contortions and exasperated sighs (though I did have sympathy at times) looked more patronising than wise.

Cohn-Bendit started with the personal attacks by questioning Ganley’s links with US military giving the Irishman the opportunity to read a not very edifying passage from Cohn-Bendit’s book (Le grand bazar). If Cohn-Bendit had stuck to political issues, I feel he could have skewered Ganley on substance (or lack of).

As it was, I think I can say that most of the audience, apart from the Libertas clutch at the back, left after the two-hour debate absolutely none the wiser about Ganley’s or Libertas’ policies. This was partly due to poor moderation on the chairman’s part (Paul Adamson from the Centre thinktank) but also, it seemed, a deliberate tactic by Ganley to not commit himself to anything at all.

Still, I am pleased there was a debate at all. For such a political city, Brussels has remarkable few head-to-head sparrings between politicians – the European Parliament offering only choreographed for-the-record comments from a pre-defined list of speakers.

I hope it will herald more. I think each political party should put forward a candidate for European Commission president and they should meet in this format to debate one another. Such debates might give people a sense for what they are voting for when it comes to the European elections. 2014 perhaps?

To some in Brussels, Ganley is the devil himself. Charging around, upsetting the political apple cart with loose talk about the treaty all the while claiming to be pro-European. To others, Ganley, who wants to be an MEP, is bringing a welcome edge to the EU political debate ahead of the European elections.

But still he remains an unknown entity in the EU capital. While most have read about him – the Irish businessman who spearheaded a successful campaign against the Lisbon Treaty resulting in Ireland’s no vote last year – few have heard him speak, let alone debate.

He will be facing one of Brussels’ best known politicians. Cohn-Bendit, of 1968er fame, is strongly pro-European, highly opinionated, and a good debater. Ganley, who only recently made the switch from the boardroom to politics, has yet to show himself to be in the same league.

Still I am looking forward to the meeting. Ganley, I feel, is indeed tapping into a swell of people who feel alienated by Brussels. But I don’t think his one-horse campaign – table-thumping, slogan-filled but ultimately lacking in ideas as it is – is the answer.

At the recent unveiling of Libertas’ Brussels office – in which he harangued journalists like they needed to be converted to his politics – the party’s list of ‘principles’ consisted of a ragbag of ideas including less EU meetings, making MEPs’ expenses public and reducing the Union’s annual budget. There was little of what Libertas stood for and much of what it stood against.

So let the gloves come off on Wednesday – but let it be a debate on substance…