Even with Precheck, the hassle of dealing with the TSA at US airports is incentive enough to question whether or not some trips are worth taking by air rather than by road or rail. I could just as easily fly as drive on some relatively short routes, but I may choose to drive just because it involves reduced variance in times. A 3-5 hour drive or a flight with 20-45 minutes in the air? Given the TSA screening checkpoint could take as little as 30 seconds to clear to as long as 30-60 minutes, planning for what the TSA experience may be like just acts as additional incentive to consider driving rather than flying. Even when the financial costs of flying are the same or lower than the cost of the road trip.