When Scotland’s next generation of modern studies students is asked to explain the main reasons for the abject decline of the Labour party in Scotland, the possible answers should be offered in a multiple-choice format. The major problem facing the examiners would be: which options to leave out.

I suspect many would be tempted to plump for the one about the ruinous sense of complacency that had settled upon the party towards the end of the 1990s. This was evident in the conduct of some of its superstar MPs who felt that a long-distance relationship with their constituents was sufficient to maintain their support. By the time the SNP had got its electoral machine in full running order in 2011, Labour was desperately handing out satellite navigation systems to some of its big beasts for the purposes of reacquainting them with their neighbourhoods.

You’d also want to consider an answer built around the Scottish independence referendum of 2014. This was when many of these party stalwarts chose to wrap themselves tightly in union flags and cheer manically with their Tory chums when the result was announced in the early hours of 19 September. Some of them were then wiped out at the 2015 general election and went on to take ermine and big consultancy jobs with those firms that advise billionaires how to “make the most of” their riches.

During this period and beyond, the leader’s chair in Scotland was fitted with an ejector button for easy dispatch. One of them was even found to be an adviser to the neo-conservative thinktank, the Henry Jackson Society. It was about this time that rank-and-file members began asking who had abducted their party, as they scanned the skies above Bonnyrigg.

Meanwhile, the current leadership, like its puppet-masters south of the border, has yet to formulate a coherent opposition to Theresa May’s Brexit strategy three years after the EU referendum. You could devote an entire semester to this study of how easy it is to lose a political party in broad daylight.

Almost 12 years after it first lost power at Holyrood, Labour in Scotland is now becoming a boutique party like the Scottish Greens. Little of what it says or does is of any real consequence other than to make the Holyrood debating chamber look busy and diverse. Last week, party chiefs were moved to issue guidelines, including a cut-out-and-keep script, on how to approach party members threatening to quit. Several thousand have done this in the last year and if the haemorrhaging continues at this rate the party north of the border will be holding its next annual conference in a cordoned-off area of Caffè Nero.

Labour is becoming a boutique party like the Greens. Nothing that it says or does is of any consequence

The advice on how to stem the flow of departing members starts reasonably enough. “Start by introducing yourself and explain you’re calling from their local party. Let them know that you’ve noticed they have recently resigned from the party and ask if they have a few minutes for a chat about their resignation and it won’t take long.”

What follows is an anodyne and slightly condescending begging letter in the style of your local tennis club politely informing you that your membership is about to lapse. I’d be urging a much more direct and robust missive that seeks to address the real issues, something like this:

“We at Labour HQ were distressed to learn you intend to resign your membership. We’d like to thank you for your years in service of Labour. This party and our partners in the trade union movement have been solely responsible for delivering the majority of people from the servile existence that had been their lot until 100 years ago. We brought you the NHS, proper educational opportunities, better housing, decent pay and conditions at work, pensions and workplace protection.

“However, today we hold up our hands and admit that recently we’ve taken our eye off the ball, completely fucked up the party and acted like pure fuds in the process.

“Having got that out of the way, here’s what we intend to do, by means of redress. We solemnly pledge to ensure that no elected member of the party will ever be seen again on a stage with the Tories, the party that opposed each and every one of the social reforms we have protected. The penalty for breaking this law will be a lifetime suspension from the party.

“Further, we pledge to cease our childish and immature opposition to an independent Scotland. Labour is a broad church and we must accommodate this entirely reasonable aspiration that has become the favoured choice of tens of thousands of our former members.

“When we seek to scrutinise the SNP’s record on health and education at Holyrood we promise in future to get our numbers right and thus to cease, forthwith, the weekly routine of getting our arses handed to us in the chamber.

“In accordance with the founding principles of our great party, we are committing ourselves to restoring clause IV as the moral framework for all our future undertakings. Thus, we will immediately seek to bring all our great national assets, which once served this country well, back into public ownership and free them from their current primary function of lining the pockets of overseas investors.

“We enclose our proposed laminated new membership card, which has the words of clause IV printed on the back.

“Arise this party from its slumbers.”

• Kevin McKenna is an Observer columnist