Jury Jone...
http://en.wikipedia.org/wiki/Path_of_least_resistance
Don't you think that the upper mass' momentum coupled with inertia and the fact that below it is a rock solid 70+ floors of undamaged building with 47 core columns, floors and steel outer columns... would propel it off to the side of the building (where there is no resistance) instead of down and through a structure which had the ability to support (massive resistance) the weight of the upper mass?
HAHAHAHAHAHAHAHAHA!
Oh, sorry... wait a minute...
HAHAHAHAHAHAHHAHA!
Wait...seriously...
HAHAHAHA!
OK, let me ask you...
Was the WTC solid inside? Someone once told me that children, before they learn about anatomy, are convinced that humans are solid inside, like a potato. Was the WTC a potato? Was it a tree? If not, please don't talk about "rock solid 70+ floors of undamaged building".
Secondly, what makes you think the core was undamaged? In my
very simplified picture, I did not include the core columns. Do you have any idea why? Hmmm? It's because, if they did not fail, there would be no tilt. You'd have the outside intact on one side, and the core intact, and that would be enough to keep the upper mass from tilting. Are you familiar with the term "fulcrum"? If not, then perhaps you should return to third grade.
It's not the weight of the upper mass that crushed the lower floors all the way to the ground... it was the energy released by the 50 foot? fall that generated so much force that it smashed through almost 10 floors per second all the way to the ground. Note: And why were all four sides of the build exploding so symmetrically... in such a chaotic event i.e. tilting upper mass, scattered rubble... would the energy be so perfectly distributed throughout the entire collapse?
Perhaps it was the asteroid that would hammer the WTC into the ground like a nail.
Also, if you tried to visualize this growing upper mass, whose increasing size supposedly increased the speed of collapse... you wouldn't come up with a single object i.e. the upper floors melded together with the collapsing lowers floors... wouldn't it be more like the upper mass, and then millions of pieces of individual rubble caused by the collision between the upper mass and the lower floors? You all talk like this increasing mass was the upper floors literally fusing together with the lower floors as the collapse progressed. See: this is why it's important to visualize things... as it helps you understand the relation between your theories and a real world environment.
Once again, you seem to think that a pound of steel and a pound of talcum powder provide different amounts of kinetic force as it lands on the lower floors. A pound is a pound is a pound, and 100 thousand tons is 100 thousand tons, regardless of whether it's intact or not.
Also, your illustrations...omit one key component... and that is the 37 non-severed core columns that were still running from the base of the building through the impact floors (that big white gap - BTW did you borrow these pics from the 9/11 commission report) and up to the roof.
How did all of these columns manage to simultaneously break in a split second? How can three (sides) outer columns significantly affect the balance of the core columns in such a short span of time? I can see if the building was hollow... if that were the case, than obviously the three sides failing would of caused the imbalance required for the upper floors to tilt over... but, it all comes back to those core columns... and how they actually failed. This is an event that still doesn't have any logical explanation.
If you are gonna reply... please don't interject some really abstract term like, transferring of loads... which is so broad... that you could use it to explain away almost any event and/or phenomenon.
Yea, the WTC 1 & 2 fell because of the way the upper mass' latent energy penetrated the towers' terminal resistance threshold. Are you that dumb... please go read a book and learn something.

Man, you crack me up.
Oh, by the way, how about addressing how the upper mass was suspended in the air for three seconds before following the lower floors to the ground.
Sorry I'm not on the 'net at the same time you are. I have to catch up on these things after the fact.