RE: Weasel words?
Its interesting that the authorities are going back to the certification process to look for faults. Some of these problems sound like QA issues (fuel lines not properly installed, etc.). On the other hand, if these are issues with design, the "787 type certification", that could be serious.
There are design issues that do crop up in the manufacturing process. The design looks good in analysis and in testing, but it just can't be replicated in manufacturing reliably. That would call into question the whole "design team" philosophy Boeing advertised, where members of manufacturing sat in on preliminary design meetings to identify those that were unproducable. It may turn out that these were exercises in getting manufacturing to keep quiet about bad engineering once it hit the shop floor. And they (mfg) didn't buy in. I saw quite a few instances of that when I did my time at Boeing.
The other "type certification" issue is that Boeing doesn't own much of the design process anymore. Some of these problems might be chased back to Boeing's partners. And if the system requirements and contract language were not written without loopholes, the required changes will cost Boeing a bundle of money. That will get some push back from Boeing as not "encouraging aerospace trave", one of the FAA's roles.