Next Left's Sunder Katwala knows a thing about political publishing, albeit of the academic kind. We first met when I was at Politico's and he worked for Macmillan. He's written an article headlined WATT'S THE POINT? on Next Left this afternoon, which I think deserves a full reply, partly because he is under a few misapprehensions and partly because I think some of my readers might be interested in a few facts about the world of political publishing.

Let's go through his assertions one by one...

1. Will Dale say what his initial print run is? I would be very surprised if it were over 2000 copies, and would guess it more likely to be less than half, or even a quarter, of that. (Pitch it low enough, and you could announce a sell-out and a reprint by next week!). I shall ask him.

Ask and ye shall receive. I think Sunder must be basing his estimate on his former world of academic publishing, where Macmillan would print 500 copies of a book and price it at £50. Print runs are a publisher's worst nightmare. On books like this you run the risk of getting it badly wrong. Back in 2000, the publisher of Edwina Currie's diaries printed 20,000, but had to pulp two thirds of them. The booktrade is very different nowadays. Sales are concentrated on three outlets - W H Smith, Waterstone's and Amazon. This means margins are far tighter and pricing is more competitive. You know that if you sell a book at an RRP of £16.99 each of those outlets will know between 30% and 50% off it from the word go. Economic madness, but there you are. We have pre orders for 8,000 copies - far more than I ever expected. There's no guarantee that all those will sell, but the fact that the book, after a mere 24 hours, is in Amazon's top 10 biography list and is about to enter its Hot 100 sellers, gives me confidence in its performance.

2. I imagine the publisher and author would be in profit, though this will surely primarily depend on any largesse received from Mr Paul Dacre's chequebook rather than the great book-buying British public.

Not true from the publisher's point of view. It's normal that the author keeps the lion's share of any serialisation money, so our profits are very dependent on book sales.

3. The main impact - the whole point - of such an exercise is the media and blogosphere political detonation. The book (co-authored by the Sunday Times' deputy political editor Isabel Oakeshott, making their non-serialisation of the book interesting) is simply a vehicle. It is certainly the type of serialisation which makes buying the book pretty redundant for any but the most dedicated anorak.

Again, a total misreading of motives. Peter wanted to get his side of the story out. My interest in this book is commercial, rather than political. I took it on because I thought there was a fair chance of turning a profit on it. I hope to be proved right. Biteback is not a company with a political viewpoint. I'd be very happy to publish a similar book from a Conservative if I thought it would make a profit. We're publishing Nigel Farage's memoirs, which I imagine will not go down well with the Tories. I've commissioned three books relating to the LibDems recently. We're publishing a series of 7 books prior to the election called WHY VOTE? One book each for Labour, Conservatives, LibDems, Greens, UKIP, SNP and Plaid. Each party has been happy to cooperate. I do not expect the latter four to make a profit - we're doing it because we think it's a good thing for politics generally to have done it.

I have read the book. Sunder hasn't. It is most certainly not a book just for political anoraks. There's a real human story which hasn't come out in the serialisation so far. But he are right in one respect. If people feel they've read it all in the paper, they may not buy it. But bear in mind a serialisation is usually a maximum of 10,000 words. This book is 85,000 words long. And there's gold on virtually every page!

4. If the tell-all memoir of Peter Watt would have not been an obvious candidate for the list of a mainstream publishing house, one might then observe the success of several key players from Britain's political right (particularly the Ashcroft-Montgomerie-Dale triumvirate) in realising the value of creating alternative media channels to make such interventions possible, through whatever combination of strategic funding and individual initiative is involved.

I disagree. I think a mainstream publisher would have seen exactly the same potential for this book as I did. And I know from emails I have had today that there are a couple of them who wish they had had the chance to sign it up. Peter and Isabel came to me because they thought I would know how to market a book like this and they would get personal treatment from me rather than being handed round from department to department in a big publisher. They also presumed we could act quickly, and they were right. I'm not sure what either Ashcroft or Montgomerie have to do with the price of fish here. And I don't think my personal online presence played any sort of role in their decision to sign up with Biteback at all.

5. Whatever Watt's motivation - ego, financial gain, personal revenge, or a botched attempt to participate a weekend late in a farcical coup would all seem to be among the possible contenders - very few in his own party will thank him for his final destructive contribution to the party's general election effort.

Peter can speak for himself, but I have detected no sign of extreme bitterness of revenge in our conversations. He had a story to tell and wanted to tell it. This was the first real opportunity he has had since he was cleared by the Police. A book like this takes a long time to write. He's certainly not motivated by money. If he and Isabel had been they would have gone to a publisher with deeper pockets than us. The point about the botched coup is facile. No one knew it was coming. It would have been virtually impossible to plan the publication and serialisation around such an event. The publication date was set a month ago, and the serialisation was agreed shortly before Christmas. No conspiracy here, honest.

Of course there will be few people in the Labour Party who thank him. He never believed there would be. He would tell you that I went out of my way to warn him about the bile and venom that would come his way. The vicious Tweets that I have been seen today are evidence of that, but he and I both know that people react in this way when they know in their heart of hearts that there is truth in what is being said.

Peter feels a deep loyalty to the Labour Party, but that loyalty has been terribly abused. As he tweeted last night "loyalty is a two way thing". He is still a party member and donates money to the party. It is not his fault that the people at the top of the party he still loves treated him in such a terrible manner. And it is his right to tell his story of what happened, as there are clearly still people out there who believe that Gordon Brown was right to brand him a criminal, hours after telling him on the phone that he would "look after" him.

I am proud of the way we have published this book. And I hope it sends out a signal to anyone out there - whatever their politics - that Biteback is becoming the place to go to publish decent political literature. Take a look through THIS LIST of our upcoming titles and I think you'll be surprised at both the quantity and the quality.

So if you have a book idea, you know who to contact!

UPDATE 8.15: The book has now entered the Amazon Hot 100 and is number 8 bestselling biography.