I think one of the key problems with the overall layout was the desire to run a toll road that connects TX-183 to the northern highways through the airport, and

I think one of the key problems with the overall layout was the desire to run a toll road that connects TX-183 to the northern highways through the airport, and to use this road as the two entrances. They still could have designed the individual terminal layouts better though, as the road and garage layout of Terminal D shows.