Thanks for the advice.
We decided to score the race without the sailor seeking redress.
Then we ascertained where we thought he would have finished without the
incident, then gave him the same points as the person with that placing in
the race.
Seemed to be fair all round - didn't penalise those with a good position in
the race but also didn't penalise the person seeking redress.
To abandon would have satisfied the minimum number of sailors.i.e. those with
indifferent results who wished to 'bin' the race.
Thanks for your input, gratefully received,
Andy