It is interesting to compare the Dominic Gates article from the Seattle Times with the Qantas 72 report. If you're not familiar, QF72 was an A330 that experienced multiple pitch upsets at cruise back in 2008. Several injuries and a successful diversion. The problem was traced to random data spikes from the No. 1 ADIRU. It's a great report; only one I know of that discusses system safety assessments in detail.
That said, consider this: In the QF72 report, the ATSB said: "The A330/A340 FCPC algorithm for processing AOA data was redesigned after a problem was found with the initial algorithm during flight testing that was conducted before the aircraft type was certified. The redesign unintentionally introduced the design limitation in the algorithm, and the fault-tolerant features of the system were not able to fully mitigate the problem. The design limitation was not identified during the redesign activities. Although the SSA identified the relevant failure condition (incorrect, high AOA data leading to a pitch-down command), it did not identify the scenario that led to this condition on the 7 October 2008 flight. The results of the SSA and other design evaluation activities can be summarised as shown in Figure 54."
In yesterday's article, Gates said: "The original Boeing document provided to the FAA included a description specifying a limit to how much the system could move the horizontal tail - a limit of 0.6 degrees, out of a physical maximum of just less than 5 degrees of nose-down movement. That limit was later increased after flight tests showed that a more powerful movement of the tail was required to avert a high-speed stall, when the plane is in danger of losing lift and spiraling down."
The QF72 report also discusses the complete absence of human factors considerations in the design room, as opposed to the cockpit. Airbus missed the alteration to the safety assessment created by the change in software during flight test. It strikes me that perhaps Boeing did the same…also during flight test, and possibly for the same reasons. Food for thought.