Preparing for my conversation with Nick Clegg at this year's Guardian Hay festival results in a huge flow of questions from family, friends and colleagues – as well as from readers of Comment is free.

If the questions had a central theme it was: who is Nick Clegg? I was surprised by the level of interest. My three children (15, 13, 10) all wanted to meet him. ("Dad, is 30 a big or small number?', my 13-year-old daughter asks, a question that will not be put!) Two of their friends stayed on for an extra 24 hours just to hear him.

Some involved with the festival were concerned that he would face a hostile audience, but the reception started warmly and grew warmer. Concerned that I would be accused of letting him off too lightly and warned by Simon Jenkins to cut off his flow, one of my numerous interruptions eventually generated cries of "Let him finish! Let him finish!".

He charmed the audience, he came across as smart and passionate but not "a man of the left" ("I'm a liberal"). He easily won them over. He has grown immeasurably as a politician since I first met him three years ago, when he used to complain that he couldn't get his message across. He seems entirely comfortable in his new job, even if he didn't want to own up to enjoying the first month.

What about substance? In such sessions the interviewer is caught in a dilemma: do you go micro on two or three big issues, digging in depth, or do you skirt across a wider range of issues and deal with more, but only superficially? It's a difficult balancing exercise. This audience wanted more, as the range of questions made clear, from parliamentary reform to school closures and a raft of issues in between.

On the processes of how the new government came about, we got insights into the timing. But I doubt his answer will satisfy the question from Toonbasedmanc: what would he tell 11,000 Lib Dems voters in Hexham who voted Lib Dem to keep the Tories out?

If people wanted a perfectly pure outcome at the election, Clegg said, that's what they would have voted for. "To those who want purity, go out and campaign for purity ... I believe in pluralism."

And he swatted away Clive JW's question on being in coalition with a Tory party that had spurned moderates in the European parliament to climb into bed with what Clegg called during the campaign "a bunch of nutters, antisemites ... and homophobes". There was no bed-sharing in Strasbourg or Brussels.

He was careful to avoid substance on issues that are in the pipeline, like possible rises in VAT (I would predict from his answer to my question that they are coming) and the timing of major legislation on constitutional reform, including a vote on AV (it will be less than 13 years!). And we know it's likely that big hikes in university fees are on their way, and that there is no clear plan about what to do to guarantee mobility for prospective students from poorer backgrounds who won't be able to afford expensive, city-based universities.

On foreign affairs he was more expansive. It seems the use of military force in relation to Iran is not off the table, as the Lib Dem manifesto urged. And in response to a question from Gandolfosreturn, Israel may be subject to increased pressures, Clegg said, including possible economic measures, to end the Gaza blockade on humanitarian relief.

On the Chilcot inquiry on the Iraq war, there was a major development: a clear commitment to make sure that the inquiry is able to publish a great number of documents: the current protocol on a presumption of confidentiality and secrecy will be changed to a presumption of publication, but most likely to coincide with the inquiry's report, whenever that may be.

It was a polished display, and judged by audience some audience members I spoke to one that was perceived as frank and honest. "It wasn't dull and it wasn't a performance," a leading light from the world of theatre said to me. "That's what I liked about it."