Engpil,
Your post raises a couple of quite relevant questions, and merits a few clarifications.
The clarifications first. It's probably a generalisation to say that all software has faults, though it is fairly likely of any non-trivial system.
Also, safety critical software, in particular that which may lead to loss of life if it fails is incredibly resilient if developed correctly. The current benchmark is less than one failure every billion hours. i.e. over 100 millenia
Obviously things have moved on since the 80's, but even then safety critical software developed with the appropriate tools, methodology and management should have been more than adequate for the purpose.
Having said this all, we need to concern ourselves with the systems in question. I think the team auditing the system had a fair understanding of the issues, and would have been shocked to find the mean time between failures measured more appropriately in minutes rather than millenia.
Back to the questions.
Are the software issues a significant factor?
Yes, clearly, in different ways. Firstly, they do provide a possible cause for the accident which cannot be ruled out for the reasons you suggest.
Secondly, they demonstrate that the aircraft was not airworthy and should not have been released to service. I do not find it credible that anyone can look at the known evidence with an open mind and not see this.
Following on from that, with what was known at the time, was it acceptable to sign the RTS? I personally believe this goes beyond Gross Negligence as it must have been a conscious decision.
Anyway, keep up the good work all. Hopefully someone will remind DC of his promise when the dust settles...
TN