Why on earth is there always this pointless speculation.
One reason may be that because the AAIB reports take time to be published people need to think things through so that, heaven forfend, they are faced with a similar situation they may have a little extra knowledge to help prevent a repeat of whatever event is under discussion. It's a bit like a staff room chat on line mulling over events of the day. There will always be those who post who haven't a clue but still consider that they should pontificate on events but the ones who really know what they are talking about have the facility to correct errors.