Actually, it's simpler than that.
The quote that "the Towers would likely remain standing" is based on the
preliminary models -- and also doesn't mean "likely to remain standing forever." It actually means that, under those cases, the Towers would still have collapsed, but it would have taken longer than it did in reality.
As it turns out, the fuel loading is actually not that relevant. More relevant is the fuel
placement, and how the fuel load determines the location -- not the intensity -- of the fires.
An increase in fuel load from 4 lb/ft
2 to 5, i.e. 25%, is small compared to the increase that was tested during model sensitivity testing. That sensitivity testing, in which the fuel load was increased by 33%, found that the fuel load was relevant but only with respect to the duration of fires. See NCSTAR1-5F section 5.2 for the sensitivity analysis.
The overall effect of fuel load on the fires is described in Chapter 6 of NCSTAR1-5F:
In Case C and D, of course, there was no change in the combustible load at all:
Therefore, the complaint about increasing the fuel load in WTC 1 is groundless, and stems from lack of comprehension about the report.
It is similarly incorrect to state that the fuel loading
or placement defined Cases A and C versus B and D. More importantly, B and D involved
more impact damage, especially fireproofing damage. That makes a far greater difference than any change in the fuel load.
The reasons to prefer the higher impact damage estimates are given in NCSTAR1-2B. We've discussed them to death in
this thread (skipping most of the crap in that thread), and besides that cases B and D were seen to better simulate the leaning and floor behavior than cases A and C. This is why A and C were rejected:
For more information about this, please see Chapter 7 of NCSTAR1-6.