I dont understand the controversy. !600m for a 738 wet is close to or out of limits with a ldg wgt of ,as been pointed out, between 55 and 60. A runway doesnt have to be contaminated, wet is enough. Anyone who operates into short strips will tell you. As for commencing the approach..well the commander may have been at a wgt that allowed a landing in his PI but with fine margins. During the approach there may have been a tailwind down to 50/100 feet This would negate his calcs and necessitate a go around or change of heart. The boeing pi is very generous, but maybe tf have a policy of factoring all pi calcs , some do, although under jar1.50 its not a requirement. Actual ldr will do in the air. The crew were paid to make the most conservative desision. they did for safety. Perf A prevents accidents with a probability of 10 to a power of-8, ie conservative. Making a give it a go anyway decision reduces those odds. I operate regularly in an 800 into short strips. It can be a butt munching job with other than cavk calm. you have to fly as per the ref plus factor u calculate and land as per boeing to validate your decision and calculation. An incident following a departure from this would cause more havoc than a feckin bus ride.
So microsoft types et al, unless you spend your days tired, making judgemnet calls, concerning the safety of 189 other people butt out and go play.As for the alternates the preffered alts will be on his or her plog in order of preference. TF have the right to send their aircraft where it suits them vis a vis the easiest logistics. EG liverpool is closer to man than egnx and is our prefferred alt, but divert there early in the morning and youll be sitting waiting for a reserve crew because there arent the busses facilities or handling spare to help. So east mids, brum or even lgw is better, for new crew, infrastructure or whatever the recovery programme or tactic may be.. nuff said, its a non event.