Well there were a few points raised by his Honour in the judgment but is it fair to say that had the arbiter not altered his decision by "a large amount of money", the amendments would have held?
I wonder why the arbiter did it? Ignorance of the rules? Sloppiness? A change of heart? To better represent his original intention? A desire to avoid getting the lawyers back which would have added to the parents' enormous legal costs?
I guess from a legal point of view, the reasons for his mistake was not important, but it would still be interesting to know.
btw it's good to see terms being added to Flast eg. functus officio, Slip Rule