This is a little amusing because debunkers happily suggest we imagine the WTC columns being crushed like pop cans, but anyway...
The point of the 1/10" steel mast example (think of it as a very tall, very strong, pop can if that helps) is that it must be much, much, and indeed "wildly", weaker than a WTC perimeter column. We can measure the aptness of my comparison very easily by calculating the critical length of the lower section of an isolated perimeter column (i.e., consider a column that is prismatic but using the heaviest column dimensions in the WTC perimeter).
What's your estimate of how that calculation comes out? (What I tried to say earlier is that I can't learn from someone who can't, or won't, at least estimate this height.) I'm not hundred percent sure of my calculation, but I think it's at least 400'.
Now, just ask yourself whether a structural system built out of either the masts or columns, which we now know the critical length for individually, would have a longer or shorter critical length than the individual masts or columns.
The textbook example just gives a (ridiculously) extreme lower bound on how tall the perimeters must have been able to stand on their own. That bound is over 200'. I simply believe the engineers designed the shells to stand 7 times taller than that ... under strong wind and seismic loading.
The general principle illustrated by the can is buckling. Mick is illustrating bucking using a common object that does, in fact, buckle and illustrate that principle. Mick is very explicit about what he is illustrating and the limitations of the illustration.
You, however, are trying to illustrate that a complex structural system would withstand a certain, well-defined set of circumstances for which it was not designed. To illustrate that, you point to a graduate-level problem set from a structural engineering course that is presented to you with little context and math you cannot read. But even by what you can read from that page, you should be able to tell that the principle illustrated by the prismatic steel tubular in the problem is inapplicable to the perimeter walls of the towers. The reason you do not realize this is because you skipped the stage of learning that most rational, intellectually curious people would undertake called "learning the basics". If you even just stopped an looked up the term "prismatic" you'd have your first clue that you were way off base, but, if, before diving into a graduate level problem set you spent time reading about when Euler's equation can be applied and what it actually tells you, you'd understand that it cannot solve for a situation where there is nonuniformity in the strength of the column along the axis of its support. This is very basic. This is why columns are braced at their connection points. This is why NIST made a point of reviewing whether columns were severed at their connections versus other failure modes when it analyzed the debris. All of this is completely lost on you. To wit, the critical length for self buckling for a uniform prismatic tubular
cannot tell you the "lower bound" for self buckling for a non-prismatic, non-uniform structure, whether of the same or, as is the case here, completely different, dimensions. That is among the least coherent and most lacking-in-critical-thought claims you've ever written here.
You are stuck in a myopia of trying to prove your misguided intuition about how these systems would behave is correct. Even if you just actually read the NIST report at this point you'd at least have some sense for the basic principles you are completely missing. I won't and can't give you an estimate for how high the complex system would stand because I understand that it isn't a matter of intuition or basic principles; it's a very complex engineering problem for which hundreds of pages of calculations or a computer simulation would be necessary. Unlike you, I'm not staring at the problem from a place of only abject ignorance and motivated reasoning. I've fully read the NIST reports, similar technical reports, books like Cities in the Sky and even basic textbooks on structural engineering principles, so I understand that the tower perimeters were designed as the most efficient system possible for their limited role in the building under the assumption that they would be braced by the floors. The towers were so susceptible to windshear and so light compared to other tall buildings that bracing the perimeter was not a trivial project. Its designers spent over a year figuring out that problem alone and even patented new types of truss connections to make it work. But you're going to tell me that all of that work was pointless because the perimeter was so strong it would stand fast regardless. Because, after all, something completely different that is also made of steel can stand by itself for a certain height, so,
something something your belief is confirmed! Ok, sure.