No evidence DD/F caused collapse
There were fires on several floors, at different times, in the area of the initiating event.
[the failure of core column 79, 80 and/or 81]
Fires in east half of WTC 7
NIST
11:30 a.m. to 2:30 p.m.
Fire on floor 12, moved toward the east face
2:00 to 2:30 p.m.
Fires on east face Floors 11 and 12 at the southeast corner, progressing north
As of 3:00 p.m., there were fires on floors 11 and 12 in the area of the initiating event.
Some time later, fires on 8 and 13
A core column, weighing over 4 tons per floor, would have to be uniformly heated to about 1,000 F, and 3 or 4 floors would have to collapse all around that column, before it could break at 3 splice joints and buckle.
There is no evidence that the initiating event was caused by fire.
There was no debris damage to or near the area of the initiating event.
That's the evidence.
Debris damage to the other end of the building,
and fires that a burned on a few floors, for a few hours, at different times, in the area where the collapse began.
The debris damage could be broken into 3 groups.
1) the damage visible in photos and videos
2) the damage know of by eye witness testimony
3) damage not seen by anyone
1) We can agree that several columns on the south side of the building were severed, that the SW corner had the corner column and several adjacent columns ripped away to a height of more than a dozen stories, that windows were broken over much of the southern face up a couple of dozen stories.
2) We can agree that two elevator cars were ejected from their shafts at the 8th floor, that several persons mention a long , tall gash in the south face of the building.
3) We, I believe, could agree that there well may be internal damage that was not witnessed by anyone.
We know that there was a bulge in the side of the south face. It it quite apparent that a bulge means a huge degree of lateral stress is being put on the internal columns of the structure at, and just above the cantilever truss system that transfers the load of the upper stories above the pre-existing Con-Ed building.
We know that there were then fires on many floors of the building and that one of these major fires burned about the area of the (visible) initiating event and we know that steel does weaken as it is heated.
Therefore we know for fact that this building was in bad condition and that its condition worsened throughout the day.
It creaked and groaned and bulged and was subject to several major fires.
Then it collapsed.
It is too bad that you cannot believe that the violence done to this building, the insults it took, were enough to cause its collapse. However your personal incredulity aside the evidence does indeed point that way.
On the other hand you have nothing but eyewitness reports of "explosions", one occuring very, very likely while one of the towers was collapsing and the other occuring as WTC 7 itself was collapsing. You also claim that the manner of collapse is weighty evidence of something other than DD/F caused collapse when in fact it is indicative soley of a collapse that began along the centerline of the structure which cannot be said to be something that only demolitions could do.
Given all that you have said I personally would put the likihood of this collapse being DD/F, versus demolition caused, at 10 to 1 or better.