Labour has just kicked off its first big wave of expulsions, purging many voters from the party’s leadership rolls. Twitter is ablaze with activists who believe they have been kicked out because they are supporters of Jeremy Corbyn. There are, I'm told, more expulsions to come - what's going on? Is Labour purging its rolls of Corbyn supporters?

The short answer is “No”. Any conversation about Labour’s headquarters has to begin with the understanding that the party has little money and fewer staff – many left after the general election, either because their contracts expired, their bosses were defeated or because they were recruited by one of the leadership campaigns. The party has neither the personnel or the resources for a genuinely exhaustive search through the social media profiles of every would-be-joiner.

So what does Labour's the party's plan to ensure a "clean" leadership ballot, dubbed "Operation Icepick" by outsiders, actually involve? The doomsday scenario at headquarters isn't a Corbyn victory - all but one or two of the party's staff believe that is inevitable - but a legal challenge following a close Corbyn victory.

So every member of staff still at Brewers' Green has been drafted in to assist. What does the cleansing of the rolls look like?

The party has a large backlog of emails from local party chairs and individual members reporting what they believe to be voters and members who ought to be barred from the leadership. The reasons range from the clear-cut – Marcus Chown, who has been expelled today, is on the ruling executive of the National Health Action party – to the ridiculous – one member was reported for failing to attend the CLP barbecue, in a complaint that has not been upheld but at this stage in the process, all that happens is that staffers gather the evidence, and pass it up the NEC, who ultimately decides whether or not to expel voters from the rolls. (Liking or following another political party on Facebook is not grounds for dismissal – tweeting or posting about joining another political party after the election is.)

The party has also compiled a large – but not exhaustive – list of candidates, both for Westminster and the 2015 local elections, and their supporting nominations. Celebrities who have raised money for the party’s opponents – like Jeremy Hardy or Mark Steel – have also been listed.

As one staffer reflected, the problem is that “We sell Labour membership as being about values and let people forget that they have to sign up to the aims too”. All but a vanishingly small number of Labour’s new recruits are not Conservatives out to do the party harm – like Tim Loughton, the children’s minister, or the right-wing commentator Toby Young – but people who share the party’s views and outlook.

It’s not their support for the old Clause IV, but their opposition to Clause I – the election of a parliamentary Labour party against all opposition, even the likes of Caroline Lucas and Sandi Toksvig’s Women’s Equality Party – that is causing the trouble.

But there is still the potential for huge unfairness in the system. A young activist who tweets about joining the Women’s Equality Party will almost certainly be expelled. But a member of the Conservatives or Green party joining in a near-moribund local party in a Conservative stronghold – East Surrey, say, or Beaconsfield – perhaps older in years, unlikely to be on Twitter, with a Facebook restricted to say, 50 or so of their friends, will get through.

Ultimately, the operation is not going to prevent Corbyn becoming leader – and that there will be less Greens, Conservative, Ukip councillors and the rest voting will strengthen his mandate.

But the big underlying problem is the culture clash within the Labour party: not between left and right, but between those who recognise that as party membership continues its longterm decline, and voters shop around more and more, its old model, predicated on absolute loyalty, won’t provide it with the influx of talent or new ideas it will need to survive in the coming decades.