Doing "serious" now, are we?
I am not claiming any expertise at all, I am just being very skeptical about the expertise of these structural engineers and architects mentioned in this thread.
Skeptical for a variety of reasons.
One is that the statements they make are broad negative statements, they are talking about things that are "absolutely impossible".
That would mean they have tested every positive hypothesis, known ones and even unknown ones, seems very unlikely.
Another way they assert their expertise is by pointing out anomalies, but then we come to the point i was trying to make earlier, what is an anomaly in an event that happens only once?
What they would consider to be an anomaly is viewed from the framework of their professional intuition, but since this the first time this has happened, their professional intuition is not sufficient.
And there is also the fact that they feel the need to sign a petition, which makes it virtually impossible to move from their position if new data would come in.
I would trust them more if they just displayed healthy skepticism.