For, following the death of Pope Francis, it offers us an insight into what will happen behind the scenes when the Catholic Church's leading cardinals vote for his successor.

The election of a new pope is the most secretive democratic process in the world. The word 'conclave' – from the Latin 'cum clave', or 'with key' – vividly conveys its clandestine nature.

Yet when the latest conclave begins, at least 15 days after Francis's death – which gives cardinals time to reach Rome from all over the world – those eligible to vote will not in fact be physically locked into the Sistine Chapel until they reach a decision. 

Instead they will spend the night at a guest house within the Vatican's walls known as St Martha's House, where they will have the services of cooks and housekeepers plus two doctors.

Given the age profile of cardinals, even that level of medical provision might appear inadequate. Even though cardinals over 80 are not allowed to vote, the average age of electors during the last conclave in 2013 was, nevertheless, 77.

From St Martha's House, they will walk daily in their blue cassocks and red sashes to the Papal Palace or the Sistine Chapel where the voting will happen.

There will be no interviews, TV debates or campaigning. Cardinals must also avoid newspapers, radio, television and the internet. 

Even if a holy man is tempted to break the rules, they will find it tricky. Last time, in 2013, technicians created a communications blackout. The Sistine Chapel will even be swept for bugs.

The conclave proper begins with a cry of 'Extra omnes' – or 'Everybody out' – an order for non-voters to make themselves scarce. 

Those left may be there for some time. The longest conclave in history lasted 34 months, from the death of Clement IV in November 1268 until the election of Gregory X on 1 September 1271.

But in modern times, none has lasted longer than the five days – and 14 rounds of voting – it took to elect Pius XI in 1922.

It was the farcical 1268 conclave which led to the tradition of locking up cardinals until they decide. 

Then, locals in Viterbo, 50 miles north of Rome, grew so irritated by the epic proceedings that they restricted cardinals to a diet of bread and water and even removed the roof of the church.

Once elected, Gregory X's new rules said cardinals would have rations cut if they failed to decide within days. Modern conclaves tend to be far speedier. 

The conclave to elect the late Pope Francis 12 years ago lasted just two days. To win, a candidate must attract a two-thirds majority.