By Peter White
BBC disability affairs correspondent
This is going to be an anxious weekend for Ben Procter and his grandparents.
Although Ben - who is 19 and from Newquay in Cornwall - has a serious learning disability, he's been swimming to a very high standard since he was five.
Report - Paralympics consider new rules
He would have had every chance of making the GB team for the Beijing Paralympics last year.
Instead he had to watch it on television for what to him must have seemed very puzzling reasons.
Athletes with learning disabilities have been banned since 2000. Their reinstatement hangs in the balance, with a decision due on Saturday at the congress of the International Paralympic Committee in Kuala Lumpur.
This saga all goes back to the Sydney Games when the Spanish learning disabilities basketball team, for reasons which have never been fully explained, were revealed to have cheated.
A number of members of their team had no learning disabilities but had somehow managed to evade the screening process for eligibility.
Although the incident caused a chortle around the world, it was an extremely embarrassing event for the organisers.
And it has caused a great deal of distress to learning disabilities athletes who had just begun to be accepted into the Paralympic fold.
Accurate classification lies at the heart of disability sport. For it to be seen as fair and viable you have to be sure that people of equal abilities (or disabilities) are competing against each other.
Procter could be one of Great Britain's hopes for 2012
If that doesn't happen the Games lose their credibility. The ban was introduced in 2001 and a very stringent condition was imposed before it could be removed.
It's a bit like the fairytale; you know the one, where the king who doesn't really want anyone to marry his daughter thinks up an impossible task before he'll give his permission.
In this case the task was to devise a system which would not only produce a way of measuring intellectual disability precisely, but would also find a way of judging the effect of that disability on how you could take part in a particular sport.
It's a job which has puzzled academics for centuries and, hardly surprisingly, several princes have tried and failed to win the hand of the princess.
Athletes with learning disabilities have missed the deadlines to take part at both Athens in 2004 and Beijing in 2008.
But now, after rigorous testing, a dual system has been put in place which, it is believed, might do the job.
Administrators have been pretty tight-lipped about exactly how it will work, but it's now been given a trial run in two major events, including the European Paralympic Swimming Championships in Iceland.
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