Oliver. I appologise for making this post. I will cease posting here henceforth until after Lisa or a mod has respond But I feel this cuts to the heart of Christophera's proof as mentioned in the previouse post.
I owe an appology to Chris. I believe that I have found the documentary that he is talking about. I believe this is the very documentary from which he's says his irrefutable proof comes from.
The documentary is called "Building the World Trade Center" it is produced by the Port Authority of New York and New Jersey in 1983. It contains original footage of the construction of the Twn Towers. and was shown on PBS via KCET
Chris, is this the documentary that you saw?
http://www.pbs.org/wgbh/amex/newyork/sfeature/sf_building.html
The documentary is there in its entirety if anyone wants to watch it
http://www.pbs.org/wgbh/amex/newyork/sfeature/sf_building_pop_01_qry.html
If it is, your in trouble. I watched it and the only mention of a concrete wall is of the retaining wall used in the sub-basement level to hold back the water in the bay (this was also called the "bath tub"). The film also shows construction workers pouring cement onto the floor structure. It makes no mention, nor does it show a concrete core. It also clearly shows the core box columns both in aerial vews as well as floor level views as the workers were working on the floor. (It also shows that your steel worker friend would have noticed a concrete core)
Be sure to read the linked essay.
I will not post in this thread again untill a mod responds to Olivers request.
No, that is not the documentary I saw. That documentary was mentioned in the one I saw which was 2 hours in length. The 18 minute film was referred to in the beginning as a "Celebratory Documentary" relating to the completion of the WTC.
The documentary I viewed spoke of itself as the final documentation to the public of the towers and their particularly high cost, justifying that cost. It was done on a grant and started in 1987 taking three years to produce. The videographers first took every single photo and 16mm film clip and copied them all to VHS tape then logged the tape.
Copies went out with researchers who made appointments and visited contractors, designers and engineers as well as an occasional retired employees to resolve questions associated with the images they had.
The original camera people had not always recorded the date and floor level where things were shot. Sometimes a reel of film had nothing whatsoever written on it, so it was like a giant puzzle in time.
The first 20 minutes gave all that as the history of the documentary then it went into the construction of the pit, the slurry wall drilling and construction. The drilling of the bedrock where foundation reinforcements were set in the rock.
Then the foundation of the core and perimeter walls. At about this time the videographers actually imparted a sense of mystery having to do with the core. Basically the entire documentary was about the core from then on out.
The videographers eventually found the big slow down in the construction to be the butt welds in the 3 inch high tensile steel rebar which arrived in 40 foot long sticks and had to be 100% welded, x-rayed, and recoated with the "special anti corrosion, vibration" plastic coating. The videographers in talking with concrete contractors found out about forced evacuations of the concrete crews pouring floors just prior to running the steel after the corrugated panels were sandblasted. They actually had video of the crews jogging between floors after the PA and the contractor got over the conflict the unplanned or announced stoppage of work was discovered by the contractor who threatened to sue because the stoppages over a few days had cost him about $7k in wages for workers who were sitting around waiting while the PA did some mysterious thing the videographers never did figure out.
I remember the video of the workers jogging showed the PA security guys standing in the adjoining hallway next to a stack of 5 gallon buckets waiting for the workers to clear the floor.
I believe that clips of the video were sold to other video producers who made newer, sorter versions of the same construction documentary. I've met people who have seen these other productions. They were 1 hour it seems and there may have been as many as 3 of them.
the "core box columns" you refer to are not inside the core.
They surround the core When none of the demo images show the supposed 47 steel core columns, it is a done deal because those columns, if they existed, would be of the strongest elements in the towers and would be seen.
I also saw the documentary "Building the World Trade Center" at GoogleVideo but it proofs nothing about a concrete core. I´m getting sick of hearing Chris´s dissuade from real facts. In my opinion he is just fooling us because he doesn´t care about the discussion besides what he believes. 
...and he still has no proof (ETA) of the "gov-murderer" after 120 sides.... 
