KRAKOW, Poland, June 18 Euro 2012 has again highlighted the arithmetical gymnastics which teams, fans and the media must sometimes perform to work out groups when head to head records come into play but UEFA is sticking with the system for the moment.
Sunday's final Group B games were a case in point where the list of possible permutations stretched into eight paragraphs and meant fans at Germany v Denmark and Portugal v Netherlands had to repeatedly check the scenarios as every goal went in.
UEFA's official guidance for Group A included the following line: "The Czechs could even afford to draw unless Greece beat Russia by five goals or fewer."
Poland fan Sabina Kaminska said: "It is too difficult."
Overall goal difference is used in most European leagues to split up teams on the same points but UEFA favours head to head as the first differentiating factor.
If one team beats another and they finish the group on the same points, it is not complicated. But when three teams end up level, the scribbling of sums can be heard in the stadium press boxes as mini-league goal difference is being worked out.
UEFA President Michel Platini backs head to heads which are also used in the Champions League.
"For me it is correct and fair. If you have the same number of points as a team and you beat that team, you have the advantage," he told reporters on Monday.
The system certainly generates tension and Germany, despite winning their first two matches at Euro 2012, were one goal away from elimination for much of the second half in their final group match against Denmark before Lars Bender's late goal sent them sailing through with a perfect record.
Asked if the head to head rule had actually made the tournament more exciting than complicated, Platini replied: "Yes, if you are a neutral. And I am neutral.
"Perhaps the rules have to be better, we have to decide for the future but until we do, you have to respect the rules of the competition."
Italy is probably the nation to feel most aggrieved by head to heads, even though Serie A is one domestic league that does use the principle ahead of goal difference.
This causes problems during the season as teams have to play each other twice and no one knows how a table should look if two sides are level but have met only once, meaning league standings often differ among newspapers and websites.
Italy have suffered from head-to-heads, though, most notably when the 2-2 draw between Denmark and Sweden at Euro 2004 sent both Scandinavian sides through and dumped out the Azzurri.
Italians suspected a fix but nothing was proved.
"Doubts have remained ever since. It is a bad scar," said Ireland coach Giovanni Trapattoni, then Italy boss.
Italy have faced the same fear here after realising a 2-2 draw between Spain and Croatia would knock them out whatever they do against the Irish.
"They should revisit the rules because when you arrive at these situations, it always leaves doubt," Andrea Palmieri, from the official Italian fans' embassy at the Euros, told Reuters.
"We are experts in maths thanks to this. In Italy we know the possible combinations better than anyone."
Palmieri acknowledged that using goal difference might not eradicate the chance of "arranged" matches.
Not all supporters are against head to heads.
Kevin Miles, part of the England fan's embassy in Ukraine, said the Football Supporters' Federation did not have an official line but he sees no problem with the current system.
"It's not that complicated," he told Reuters.
"People will always find something to complain about if the result doesn't go their way.
"Once you've exhausted all the factors from three games, which is not that much, you've got to do it with something. Would you have a shootout?"
Penalties are indeed in the rules for when two teams who play the last match and are the only sides level just cannot be separated but the regulations also leave room for the UEFA national team coefficient ranking system.
This rewards the bigger teams who did better in previous tournaments and does not reflect the competition they are in.
At the bottom of the list of the possibilities is drawing lots.
The Euro 1968 semi-final between Italy and Soviet Union was decided by a coin toss following a 0-0 draw after extra time.