Take claims of self-driving cars being road-ready soon with a 50-pound bag of salt, not a grain.
While automakers, suppliers and ride providers such as Uber race to develop and deploy self-driving technology, one point is seldom mentioned. U.S. infrastructure simply isn't ready for cars to drive themselves 100 percent safely, 100 percent of the time.
No current federal funds are specifically committed to preparing public roads for self-driving cars. President Barack Obama proposes spending $4 billion over 10 years on autonomous driving, but that's for pilot projects, not fixing roads and infrastructure.
I'm talking about lane markings on the center and sides of roads -- many in poor condition due to age, wear and potholes -- and traffic signs and signals in disrepair in many cities.
Up to 65 percent of U.S. roads need work, the Department of Transportation estimates. To see how the DOT ranks road and bridge conditions by state, go to transportation.gov/briefing-room/dot-fact-sheets-highlight-grim-state-us-roads-and-bridges. You'll see what I mean.
If a car's autonomous driving equipment can't read the road, it might not stay in its lane.
Crisp, clear lane markings are essential to self-driving cars. Reuters reported the frustration of Volvo Car USA CEO Lex Kerssemakers when the automaker's semiautonomous prototype sporadically refused to drive itself at a Los Angeles Auto Show event last fall.
"It can't find the lane markings!" Kerssemakers griped to Mayor Eric Garcetti. "You need to paint the bloody roads here!"
Adding more expensive sensors and equipment to cars might overcome some infrastructure shortfalls, but affordability already hampers new-vehicle purchasing. That's not the answer.
Uber, about to launch self-driving Fords and Volvos in Pittsburgh, believes its proprietary mapping technology can overcome infrastructure shortcomings. We'll see.
Industry experts say the infrastructure must be fixed before self-driving cars can perform at Level 4 and Level 5 -- driving themselves in all situations.
Say all U.S. roads were fixed, repaved and repainted. And all U.S. traffic signs and signals were consistent and reliable. Even that might not enable autonomous driving.
In January, Yann Delabriere, now chairman but then CEO of supplier Faurecia, doubted governments will invest in new autonomous-vehicle infrastructure when they struggle to maintain what they have.
"Are they going to invest in electronic milestones everywhere? I don't think so," Delabriere said.
Delphi Chief Technology Officer Jeff Owens agrees that full Level 4 and 5 autonomy needs infrastructure upgrades. But he said road fixes aren't necessary for automated driving at low speeds where the vehicle can communicate with other vehicles, people and buildings.
Recently, my wife and I drove a Cadillac CT6 in heavy traffic using adaptive cruise control and automatic braking. As the car ahead accelerated, so did the CT6, keeping a safe distance. It stopped itself when vehicles ahead stopped for red lights. It worked brilliantly.
But elsewhere, the CT6's lane-keeping system was flummoxed by peeled, faded road markings.
Uber, General Motors, Ford and Delphi say self-driving cars will happen fast. But until a car can see traffic signals backlit by sunlight, until it can obey traffic cops' hand signals, until it can see the road through fog and snow, I am keeping my hands firmly on the wheel. I consider autonomous technology like the CT6's as only an occasional aid for the (human) driver.