Actually a lot of people were excessively speeding, just not towing trailers. The only reason I asked what would be considered a safe fast speed is the speed limit changes everywhere, yes for good reason but around Harris county it drops to 65, same road one county away is 70/75 and road conditions didn't change. The only reason I sped up was to see how fast he was actually going. I slowed down and thought about calling the police but didn't. He was out of sight in no time.
For those who drive the speed limit in the left lane, try doing that anywhere in the Houston area and let me know how that works out for you oh and by the way, it's actually against the law.