The rule was introduced nearly 50 years ago when playing away in Europe was a novelty, but critics say it has now become counter-productive, unnecessary and unfair.
"There was a bit of a debate about whether it has any significance today," said former Manchester United manager Alex Ferguson following a meeting of the elite coaches' forum at UEFA headquarters on Thursday.
"Some think it is not as important as it used to be.....and the attacking emphasis on the game today means more teams go away from home and win.
"If we go back, say, 30 years, counter-attacking consisted of one or maybe two, players. Today, counter-attacks have players flooding forward in fives or sixes and really positive, quick passing."
The rule, under which away goals count double if a two-legged tie ends with the aggregate scores level, was introduced into European competition in the Cup Winners' Cup in 1965-66.
It was first used in a second-round tie when Honved progressed at the expense of Dukla Prague following a 4-4 aggregate draw.
At the time it was seen as preferable to having a time-consuming play-off or the arbitrary toss of the coin which was sometimes employed and which sent Liverpool to the European Cup semi-final in 1965 after two goalless draws against FC Cologne.
In the early days of European competition, when air travel was far less developed and reliable, an away match was something of an adventure with visiting teams facing unfamiliar, sometimes hostile, conditions.
Away wins were rare and the new rule was an incentive for visiting teams to come out of their shell.
All of that has changed.
Playing conditions in most parts of Europe are pretty much identical and trips abroad no longer carry the air of intimidation that they once did. The old quagmire pitches have also become a thing of a past.
"What is helping is that the state of the pitches, pitches are fantastic nowadays, so coming out of defence with passes is much easier than it was 30 years ago, and you get a better attitude to counter-attack today than you did 30 years ago," said Ferguson.
Rather than encouraging visiting teams to attack, the fear of conceding a potentially decisive away goal often makes home teams more cautious and the rule also means that some goals turn out to be worth more than others.
"From a personal point of view, when I was playing at home, I used to say to myself, don't lose a goal," said Ferguson.
It can even border on the absurd such as in the Champions League semi-final between Inter Milan and AC Milan, when both legs were played in the San Siro stadium.
The first match ended goalless, the second was 1-1, but because AC Milan were technically considered at home in the second leg, they went through on away goals.
- Sports & Recreation
- Alex Ferguson