Is "over g" acceleration established? Or, is it a maybe? Again, "over g" for 7 is new to me.
It is established to satisfaction of many of the members here including me.
The summary history was:
1) The truth movement has established their own "meme" that free fall is a feature of CD and claims that CD does not occur with "natural collapses"
2) That belief is false and it is the OP topic of the thread.
3) For very simple systems complete removal of supports will allow the thing supported to fall at free fall
acceleration (nearly - there is air resistance but it is usually too small to matter.) So that is fact one and for
simple systems.
4) that is where the truth movement originally latched on - forgetting that anything can remove the supports - not only CD - plus reality that CD rarely causes free fall anyway - so another factor causing half truth confusions.
THEN
5) NIST reported the collapse of WTC7 with its explanation and did not mention free fall. We don't know why NIST did not comment BUT reality is that no competent engineer or physicist would regard free fall as worthy of comment in the context of chaotic collapse of a building. It is to be expected somewhere in the chaos.
6) Truther mediocre physicist D Chandler did some video measurements and measured (by relatively crude methods and approx) free fall so he "challenged" NIST and NIST responded identifying a period of free fall on one part of the north façade.
7) Chandler et all trumpeted that as if they had "forced" NIST to "admit" free fall.
8) There was extended discussion of the issue here
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9) Member femr2 is arguably the best measurer/researcher of motion on WTC collapse
10) femr2 has measured the specific bit of WTC7 North façade collapse with precision far better than NIST or Chandler and many of us including me are satisfied that one section of that façade fell at over "G"
acceleration for a brief period.
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11) Meanwhile member Chris Mohr had engaged R Gage in public debate and they agreed to set up a web site listing both sides of the debate. Multiple points - over 100 from memory.
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12) "Over G" for WTC7 was one of the points raised. I was one of the physics advisors to ChrisMohr and suggested a mechanism for how "overG" could occur.
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13) Member LSSBB (??) has recently (IIRC) commented on that type of mechanism but placed into the specific context of WTC7
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14) Earlier I spoke of "simple systems" with supports removed - the sort of thing you have been describing. Most of the reluctance - myself and others - to easily agree with your scenario is because it aint that simple once the "system" becomes "more complicated"
Hence my post 393 offer to assist you work through it.
And my suggestion that you take it one step at a time - trying to take on the full 3D FreeBody stuff within the WTC collapse context - is ....err...
rather heavy going.

...and it is a lot easier in three or four steps. I'll post you a Step 2 exercise later tonight AU - about 10 hours from now.
I don't have time now but will dig up some links to key points marked
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....some other members may assist and beat me to it.
Pleeeeease....
