DECISION-REVIEW systems in sport should come in unmarked packages carrying frightening health warnings in large print. For just as smoking offers a seductive lure to the impressionable, so does the deadly DRS to sports administrators. And once you start at either, it is hard to stop.
The one difference is that an occasional decision review, taken through the appropriate filter, won't hurt anyone. In fact, as Friday night's overturning of Alan Toovey's goal-off-the-knee showed, it can even be beneficial. The trouble is it is the beneficial one that draws you into having another, and another. And it becomes impossible to know where to stop. Before you know it you are hooked, and then there are all sorts of potential health issues.
Three king-sized decisions involving Collingwood over the past two weekends have encapsulated the dilemma. First there was the controversial incident last week at the MCG in which an intervention from off the field brought about an overrule. Then there was the Toovey case in which the umpires applied the score review process to the letter and came up with a correct outcome. Then, later in the same game, came an incident in which the off-field adjudicators applied a non-interventionist approach to a possible goal-umpiring error, in contrast to the action of the previous weekend. This may be partly due to the fact that after a behind there is less time for a consultation.
It may have been enough to warrant Jeff Gieschen doubling the size of his adjudication committee from the current quorum of eight. He might even have been tempted to phone Steven Spielberg for assistance with another re-enactment early this week. All to ensure there are no embarrassments on the big day.
While Gieschen didn't explain the purpose of last week's re-enactment of the drama at the MCG, and it was left sounding like the most futile form of self-vindication, perhaps it brought some useful insight. In seeking to re-create the circumstances of the incident in the Collingwood/West Coast game, it is possible the umpires' boss discovered a hitherto hidden truth: in certain circumstances, a television picture can convey an erroneous impression.
That would be a valuable lesson. The problem is that it only adds to the state of uncertainty now being experienced by all involved. And that, with the most exposed game of the year almost upon us.
That state of uncertainty was, I suspect, evident on Friday night.
Gieschen and his team had a lot to digest in the preceding days. That Gieschen, in discussing the previous Saturday night's incident, spoke during the week of ''probability'' was a clear indication that the intervention in that case had been a mistake. The AFL's score review system wasn't enshrined to deliver outcomes based on probability. The media release accompanying its introduction last March referred to outcomes being amended in situations in which vision is ''conclusive''.
But there was more. The AFL, with Gieschen as frontman, often - and rightly - reminds us of the importance of umpires being treated with respect. There is a crisis, we are told, in recruitment of people prepared to take on this thankless task because of the belittling they endure. So what could be more belittling for a goal umpire than to have to stand before a massive national audience - instructed to do so by his boss - with his flags crossed above his head, saying, ''I was wrong''? What could be better designed than that to deliver the message that these people are blunderers?
Perhaps that message also got home during the week because, when an incident on Friday night invited the same kind of intervention we had seen at the MCG, it didn't come. Goal umpire Chelsea Roffey adjudged as a behind a shot for goal that was touched either above or just behind the scoreline. Her problem was that the ''touch'' happened about two metres above ground level, and she had only her positioning, eyesight, and instinct to rely on. Sometimes, even that isn't enough. She may have been wrong.
But there was no review and, despite the possibility of error, I would say neither should there have been. A review would have proved nothing. The possibility that one millimetre of Sherrin-skin may have hung above the last millimetre of chalk still existed. We have to be able to live with the possibility that, at times, such judgments will be imperfect. To seek to take them into the realm of perfection - as happened on the previous weekend - is only to amplify the possibility of error. And to inflict further damage on umpires.
Yes, there are instances - such as Toovey's shot ''off the knee'' - in which the review can provide a definite answer. And this creates confusion. To review or not to review, that is the question.
If there is something of the plight of the smoker in the addictive nature of video reviews, perhaps the answer lies in a paraphrasing of the Serenity Prayer: ''God, grant me the serenity to accept the decisions I cannot change; the courage to change the decisions I can; and the wisdom to know the difference.''