The recommendation that stands out us as pilots is REC 31/04. I have always been of the view that you either take sector fuel because there is no reason to take any more, or you take (in the case of the 757) at least a couple of tonnes because the situation warrants it. In a situation where thunderstorms are forecast over a wide area including alternates 3 tonnes should be the minimum extra. I followed this policy in Britannia and was never questioned by management pilots about my fuel calculations. The extra 15 minutes holding on this flight was of no use at all.
As far as the actual accident is concerned "there by the grace of god go I" A very nasty position to find oneself in and I question whether anyone could honestly say that they would have acted differently. The only point is would the crew have started an appoach if they had another 3 tonnes in the tanks.