Traffic Ticket Talk

Most people don't know that it is not a crime in Texas to travel in excess of the posted speed limit so long as the speed is "reasonable and prudent under the circumstances." But the State starts with the presumption that a speed over the speed limit is "prima facie evidence" that the speed is unreasonable. (I explained this before here.) That being said, a conversation with someone in authority yesterday got me thinking. He said that to be traveling at a speed that is "reasonable" requires some proof that there is a "reason" for the excessive speed. That is, "reasonable" conduct means there is a "reason" for your conduct. In everyday language, is that what "reasonable" means?