Also, I'm not from Texas nor have I driven in the Houston area. I have, however, driven in many other busy metro areas. And I always ALWAYS avoid driving thru the city center. For example, I swing around Chicago on 294 instead of driving straight thru on 90/94. The traffic is just so inconsistent that I could get caught for 2 hours in a jam near city center.
I would assume the same would be true for Houston. One would drive AROUND Houston up to the airport like Google maps recommends. Is there are reason one would drive straight thru the heart of Houston to go to the airport? I feel like if you're trying to get to the airport at a specific time and don't want to get caught in traffic, you're going to avoid 69.