Yes, if the WTC fires had reached 825C, then the official myth might be slightly more convincing; however, the official report on the collapse of the Twin Towers was released in mid-2002 by a group conducting its "inquiry" under the direction of FEMA. Chapter 2 of this report is available here

Relevant passage:
"... it is well known that the maximum temperature that can be reached by a non-stoichiometric hydrocarbon burn (that is, hydrocarbons like jet-fuel, burning in air) is 825 degrees Centigrade (1520 degrees Fahrenheit). ... [The] WTC fires were fuel rich (as evidenced by the thick black smoke) and thus did not reach anywhere near this upper limit of 825 degrees. In fact, the WTC fires would have burnt at, or below, temperatures typical in office fires.

(my emphasis - sp)

For amplification on this issue, let's turn to J. McMichael, in part 2 of Muslims Suspend Laws of Physics

[...]
Now let us make a guess on the actual heat of the fire.

Fortunately, a number of studies have been done under very similar conditions. In Europe, multi-storied "car parks" are often built of steel, and the possibility of vehicle fire is a distinct possibility. A parked vehicle, loaded with gasoline, diesel, tires, engine oil, engine tar, upholstery, hydraulic fluid, etc. can cause a fire that seems very hot. A number of other vehicles could be parked close to the burning one, and they too could catch fire, with a general conflagration. Any number of cars could contain almost any household items from shopping, etc.

These materials are similar to the materials we would expect in the burning offices of the WTC: jet fuel (which is a refined kerosene, very similar to the diesel used in some European cars), oil, upholstery, etc.

A summary of the results of these studies is published on the Corus page. Go here and click on "Fire".

Individual articles are listed across the top of the window. The fourth article, "Fire in Car Parks," discusses the temperatures of "any fires that are likely to occur in a car park.

Presumably, one car could catch fire and inflame other cars parked closely nearby. As explained below, "The maximum temperatures reached in actual test fires in open sided car parks in four countries" was 360 degrees C (680 F), and structural steel has "sufficient inherent resistance to withstand the effects of any fires that are likely to occur." ... maximum temperature in the unprotected steel supports in those test fires in the U.K., Japan, the U.S. and Australia was 360 degrees C (680 F), and that is a long way from the first critical threshold in structural steel, 550 degrees C (1022 F). ... I think the case is made: The fire did not weaken the WTC structure sufficiently to cause the collapse of the towers. --end excerpt-- To summarize, the maximum attainable temperature of burning jet fuel is 825C. However, the thick black smoke issuing from the WTC fires indicates that they were fuel rich/oxygen starved fires which would have been burning at, or below, temperatures typical of office fires, or somewhere in the range of 240-360C, temperatures which are far too low to weaken structural steel. sp