His argument amounted to a New Labour apology to those in the party who felt that the creation of the idea of "Old Labour" caricatured the Labour party's enduring core values.
I think New Labour was necessary - to show that we had changed. Some of the collateral damage of that was that Labour people who were not part of that New Labour tribe felt that the party was defined against them. And it is important to admit that this was a straw man to a certain extent.
"The party - and the government itself - combined the best of New Labour and Old Labour", said Purnell, pointing to both achievements of the government like the New Deal for jobs, and the current agenda on the fiscal stimulus or the jobs guarantee.
Guaranteeing jobs for every graduate, fighting climate change, trying to go for 100% literacy and to break the link between education and family background, you could put together a very compelling agenda for people.
And sometimes its pretty hard to say which is New Labour or which is Old Labour", said Purnell.
"And, on the other side, you have people who want to say that New Labour is dead and who want to dismiss our entire record. Both sides of that are part of a debate that I think is at least a decade out of date", he said.
This had an electoral impact. Purnell noted that Labour's lost voters are, on average, to the right rather than the left of the party's remaining supporters - but suggested that the debate about heartland and swing voters had become sterile.
It is very important we don't just try to put together a patchwork of different social interests. We should look at what Obama's people did", said Purnell.
The Democrats had been too focused on communication and how to put a coalition together. The Obama argument began with values and was able to build a new coalition.
"We need to look at how to create a new majority. A lot of what Jon is talking about is being caught on the dilemma of a heartland vote and a wider vote - and we need to revisit the way we approach that whole question from the start".