They fall out and set up competing factories next door to each other, and they both manufacture identical biscuits – but one produces only the left Twix, while the other produces only the right Twix.
And while one lavishes caramel on biscuit, the other tops biscuit with caramel – and on it goes.
The humour lies in the fact that while they both make exactly the same thing in exactly the same way, they are so blinded by their narrow-minded competitive streak that they simply can’t let go of their enmity and co-operate together – despite what’s staring them in the face.
Now it might be a sign of my political naivety, but I couldn’t help thinking about this after last week’s NFU Scotland conference and AGM. Regaled as we were by the great and the good, there was definitely a whiff of the aforementioned industrial revolution biscuit manufacturers in the separate addresses to come from Scottish Conservative leader Ruth Davidson and First Minister Nicola Sturgeon.
For, while one wanted a UK-wide agricultural policy framework, with Scotland having some specially differentiated powers in order to address the distinctive needs of Scottish agriculture, the other wanted a Scottish-run policy with some UK-wide framework for certain regulatory areas in order to address the distinctive needs of Scottish agriculture.
While the union voiced calls for ideological dogma and political baggage to be put to one side, both politicians gave addresses which abounded with promises of almighty political rows and battles lying ahead over the issue of where the powers – and finances – once held by Brussels should belong after we quit Europe.
Any underlying humour in the political Twix brothers’ attitudes exited sharply stage left with the realisation that these expressions of intent were very real – and, to throw in some hyperbole, our industry looks set to be the ground zero in the Battle of Brexit, a situation which could see us facing an agricultural Armageddon.
Under the Scotland Act 1999, agriculture has been a fully devolved issue – and the Scottish Government has had the freedom to evolve and develop its own policies within the fairly flexible frameworks created by the EU.
And while the money paid into the EU came from the UK as a whole, when it was recirculated via the Common Agricultural Policy, the devolved administrations knew what their share would be – and had control of how their own budgets would be spent.
But after we leave the EU there is no financial mechanism which will automatically come into play to decide how any pot of support money is shared out by the UK Treasury. So the battle will be waged not only over who controls actual policy but also on how any funds put aside for farm support are shared out.
Now, there’s no doubt that the issue of funding should be addressed in an adult manner – but some indication of the level of priority actually given to Scotland’s farmers might be surmised from the UK government’s failure to deliver the review of the EU’s convergence uplift which, it was promised, would be completed during 2016 - but now seems to be all but forgotten by Westminster. So fears that Scotland’s needs might be overlooked are justified.
And yesterday rural economy secretary Fergus Ewing upped the ante – issuing a clarion call to all the devolved administrations to rally together and present a concerted front to make sure that they held on to their farm policy powers and purse strings.
In a letter to the Welsh and Northern Irish administrations, Ewing set out the need for a unified position on all matters no longer subject to EU law, which are currently the responsibility of the devolved administrations – including farming, fisheries and environmental protection.
Stating that these powers should remain in Belfast, Cardiff and Edinburgh, he said the UK government wasn’t listening to the devolved administrations.
So, it’s beginning to look like the battle of Brexit could be a long, drawn out war of attrition.