WT, you must have made that trip sometime between midnight and 5am.
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Dallas (for that matter, the whole DFW Metroplex) has the worst, most inadequate freeway system of any major U.S. city I've ever driven in. For instance, I know of no other intersection of two Interstate freeways on the edge of a downtown business district where you have to exit down to the city streets to go from one to the other--which is what is required to get from I-35 northbound to I-30 westbound, or to get from I-30 eastbound to I-35 southbound.
Back in 1997 (or so I am told...I was still living in Houston then), the good citizens of Dallas voted a bond issue to fund a reliever freeway to run north-south parallel to I-35 from downtown Dallas to (I think) I-635 on the north side of the city. To date,
not one spade of dirt has been turned to build that reliever freeway, and evening rush hour in both directions in this section of I-35 starts about 4pm and lasts until after 7pm some days. And, that is excluding delays due to wrecks or other non-vehicle obstructions--such as freeway repair crews.
P.S. I agree that those who downplay the effect that the fall of the WA will have, are just like the little boy whistling in the dark. As swamt stated, if AMR wasn't concerned about the possible effects, why have they spent millions of dollars prior to this fighting every single expansion of the WA boundaries? I was based in STL at the time that AMR decided that they no longer needed to provide much non-stop service from STL to the rest of the United States--that our customers didn't mind in the least having to change planes in DFW or ORD to get anywhere. Within a short period of time, you couldn't stir the guys/gals in suits carrying computer bags in East terminal with a baseball bat--all of them paying the extra $25 to board first and have prime seat selection.
As friends of mine at STL who used to work for Eastern, Pan Am and Braniff say all the time..."I've sung this song before. I've danced this dance before. And, every time management ignored all the warning signs and operated as if we were too big to fail."