In Choosing A Leader, what remains one of the best books published on British leadership contests (although I appreciate this is a niche market), Len Stark argued that the procedures parties used when selecting their leaders rarely made much of a difference. With a handful of exceptions, he demonstrated that the same candidate would have won, no matter how the party went about making its choice. Parties chose candidates who will unite them, he argued, after which what mattered was who was most electorally appealing or most competent – and they did that regardless of the rulebook.

Yet there were exceptions, not all of them inconsequential. Stark’s book was published in 1994, and even then the outliers included the 1975 contest from which Margaret Thatcher had emerged victorious. A more recent list of exceptions would also have to include Jeremy Corbyn’s victory in 2015.

Stark’s argument almost certainly applies to the changes reported to be contemplated by the 1922 committee in order to reduce the number of people now putting themselves forward to be Tory leader. Earlier in the week we were up to for enough for a football team; we’re now beginning to populate the subs bench too – at 12 candidates. The 1922 are said to be thinking of raising the number of nominations required from the current two – a proposer and a seconder – to ten or so. Thresholds like this could matter, but in this case while it might winnow out some of the less popular candidates, anyone who can’t get ten people to nominate them isn’t likely to be in with much of a chance of winning in the first place. It may not even especially speed things up. After the first round of results are announced, the rules require the bottom-placed candidate to drop out, but in such a crowded field there would anyway be considerable pressure on other poorly-performing candidates to drop out to expedite the process. These changes will almost certainly be of very marginal consequence.

Stark also showed that leadership contests tend to boost parties’ poll standings, which given current Conservative polling and equally dire actual electoral performances won’t be sniffed at. Look at the two most recent occasions when the Conservatives have changed leader while in government. In 2016 the very last poll carried out before Theresa May became party leader had the Conservatives a mere one percentage point ahead of Labour; the very first poll published after she entered Number 10 put them ten points ahead. In 1990 the arrival of John Major in Number 10 took the party from trailing in the polls to the lead. One poll in early November 1990 had Labour more than 20 points ahead; on 28 November, after Major had become Prime Minister, a Harris poll gave the Conservatives a double-digit lead.

There may be a similar poll boost this time – from such a low base, it would be worrying for the party if there was not – but there are good reasons to think it will not be comparable in scale. The problem this time is that while the personnel (and accompanying tone) may change, the policy challenge will not. Major, for example, came in promising to review the poll tax, and while this was not an easy task, it was achievable. He also enjoyed a comfortable majority in the Commons, which enabled him to move swiftly to implement the change; May’s successor faces a problem of much larger magnitude and has no such freedom of manoeuvre.

Worse, the leadership campaign may serve to close down what very limited room for manoeuvre exists. You can, if you like, believe that the only thing preventing the EU giving us a different/better exit deal is that Theresa May was just not stern enough with them, and that when presented with a true believer, someone who is prepared to play hard ball, the EU will crumble where previously they have been unyielding. Perhaps the threat of a no deal Brexit, if the new Prime Minister looks like they really mean it, will make the EU change their minds, despite the fact they have explicitly said they will not. I doubt it, but you may be right. In which case, there is an easy way out of this. The new PM and the EU agree a new deal, sans backstop presumably, which Conservative MPs and the DUP can support and it’s all over by 31 October. But if this isn’t what transpires, what then?

There is the option of no deal by default – but given the parliamentary arithmetic it looks as if the Commons might block that. The IfG briefing, which is often cited as saying parliament can no longer prevent no deal, in fact says parliament will find it difficult to do so unless the Speaker chooses to be creative in how he interprets convention and procedure. On such matters John 'Highly Creative' Bercow has form, has already made it clear where he stands, and besides the same briefing points out that one option that may prevent No Deal is for a handful of renegade Remainer MPs to bring down their own government. Other options out of the impasse might involve a referendum or an election or yet another delay (although the last might only be granted if it involved either a referendum or an election). None of this is easy or straight forward, and could go badly wrong – but these options would at least involve movement.

Yet with clear majorities of Conservative grassroots members being in favour of No Deal and against a referendum, the pressure on leading candidates to rule these out will become massive, at least for those who get through to the members stage of the contest. Ditto for the pledge to have left by 31 October, which is ambitious (to say the least), yet which several candidates have already taken as a hard deadline. In every hustings, candidates will be asked about this – and asked to rule them out. It may well be that the key thing to come out of this contest isn’t the person elected – but the way in which, whoever they are, the process of the election contest constrains their future options.