It is being repeatedly mentioned that no significant water/ice was found in the fuel. However ice melts, water evaporates, and a significant amount of fuel leaked out before the investigation began. Could this possibly explain the lack of evidence? Whatever was the cause it seems to be very illusive with no obvious evidence left behind. Water/ice seems to be the most obvious explanation for such a lack of remaining evidence. It is only natural then that a lot of suggestions as to possible causes involve the most likely culprits.