lomapaseo (and PJ2):
In order for the Lauda reverser to deploy it needed to have a malfunctioning stow/deploy valve as well as weight on wheels (two degrees of protection failed).
I seem to remember reading that the supposition in the Lauda case was that the protection in the reverser deploy electronics was circumvented by chafed and/or faulty wiring. I'm also pretty sure I remember that a modification to prevent this happening again was very quickly developed, tested and installed.
Again, regarding the calls to restrict R&N to pilots only - while I can understand it and sympathise completely with the poor moderators, you'd be preventing people who've made massive and timely contributions to these threads in the past, like PBL, bsieker and VnV2178B - and I still think there'd be a vast amount of dross in the immediate wake of incidents and accidents.
Of course, there's a degree of self-interest here as well - but I, as well as many other genuine enthusiasts try to keep to the background unless we're pretty sure we've got something to contribute, and it's a privilege and an honour to be allowed to. I for one would really hate to lose it.
In this case I think the lack of concrete information is allowing all kinds of rubbish to fill the vacuum and I hope that as proper, corroborated data is released some of the fancier theories will fall by the wayside. Those holding the BA038 thread up as an example seem to forget that the first few days were a free-for-all, with theories of computer failure, UFOs and even Gordon Brown's Death Ray doing the rounds until the dust had cleared.