Kiwiguy -
Seems like there's times when possible truths are kept from these investigations for some unknown reason. I had evidence withheld from an investigation concerning possible icing on a 737 accident as well. Ultimately, the crew was held responsible. Of course they died in the accident so were unable to defend themselves. Hopefully the FULL truth will emerge from this and ALL accidents in the future regardless of what it might cost to rectify whatever caused the problem.