The ruling was introduced by European governing body UEFA half a century ago and was trialled in the 1965-1966 Cup Winners' Cup.
It was devised as a means of encouraging teams not to play defensively in away games.
It worked a treat as the prospect of scoring a goal that would count double if a knockout tie ended in an aggregate draw forced away teams to be less defensive and more adventurous.
The ruling was later extended to national teams and it is the way FIFA and UEFA playoffs are run.
But the game has changed dramatically since those dark days of the early 60s when defensive and negative football was rife.
Today the vast majority of teams are far less inclined to park the bus than they used to, essentially because the mentality of most football managers has changed.
Being defensive today is seen as old fashioned and counter-productive: certainly a step backwards.
This is not to say that teams will not occasionally dabble with defence when they feel it is their best chance of success but they are the ones that probably would do so even if away goals counted treble.
Today's game is far more attack-minded and this positivity is ingrained in most sides at national and club level.
And the counter-attack is at the forefront of most clubs' or countries' modus operandi, whether they are playing at home or away.
In the 1960s counter-attacks used to be performed essentially by two or three men who got on the end of long passes from defence.
But today the teams that use this most effective of tactics flood the opposition with four or five men, using quick passing and movement to get from A to B.
This attitude is also helped by the fact that modern pitches are of the highest standard and they encourage attacking football because it is much easier to play out of defence than it used to be.
The rewards for attacking football are there for all to see.
So it is doubtful if today's teams would have a go in attack because of the reward of an away goal that counts double or due to the fact that attack is ingrained in their mindset.
There are many who regard the away-goals rule as cruel, unfair and even illogical. Remember, it was introduced as an artificial measure to combat catenaccio.
With catenaccio now effectively obsolete, you wonder if the rule is still as important as it used to be all those years ago.
Of course, the downside of abolishing away goals is that football would be faced with the increased likelihood of matches having to go to extra time with the prospect of the dreaded penalties.
But this is still the case when two teams cannot be separated after 90 or 120 minutes.
So why not take a drawn tie regardless of the scores into extra time and activate the away goals only if the extra 30 minutes do not provide a winner?
The cynic in me would suggest that teams that are 'ahead' on away goals could play for a draw in extra time, knowing that they would be awarded the tie. And this would defeat the purpose of the exercise, I suppose.
But the positive side tells me that this solution will rid us of a high proportion of games that are ruined by away goals, as could so easily have been the case when Paris Saint-Germain crashed spectacularly against Barcelona.
PSG won the first leg 4-0 and lost the return 1-6.
Forgetting Barca's late, late rally that turned the tie in their favour, Edinson Cavani's away goal on the hour that made the score 3-1 seemed to have killed off the contest.
The atmosphere of the game changed. You could just see it in the body language of both sets of players and a fantastic football match was nearly reduced to a non-event between a team that 'knew' it was through and another that 'knew' it was out.
Without Barca's late heroics the match would have gone down as a quality contest that ended after 62 minutes.
There have been many cases of teams' dreams of glory being dashed by the gut-wrenching away-goals rule.
We in Australia should look no further than the extraordinary events surrounding the Socceroos' FIFA World Cup playoff against Iran in Melbourne in 1997.
The Iranians were on the receiving end of a constant barrage from the Socceroos that night and only went through to the finals because the law makers chose to make away goals count double.
It was not the first time and would not be the last time this happened.