Q I've noticed new electronic signs showing up along Whipple Avenue on both sides of the train tracks in Redwood City. Any idea what they'll be used for? We're clueless.

Kristopher Rowberry

Redwood City

A No Roadshow reader shall remain clueless. These are called "trailblazer" signs and are being installed as part of the San Mateo County Smart Corridors Project. They'll be used to guide traffic off Highway 101 in the event of an incident that requires detours from the freeway and onto predetermined alternates on local streets between El Camino Real and 101. The $35 million project should be completed soon and is one of several underway in Northern California.

Last year the state broke ground on a $80 million job on Interstate 80 through the East Bay and is about to finish a $21 million project on Highway 12 and I-5 in San Joaquin County.

Q I've always wondered what you would say about my tactic to avoid rear-end collisions. It has become instinct for me to quickly turn on my blinking hazard lights as soon as I see a rapid and unexpected slowdown on the highway. I'd like to think I have helped those behind me realize traffic is slowing dramatically. What do your CHP friends think?

Drew Haaser

A Not a bad idea at the right times, says Chris-the-CHP-man: "Warning other motorists of accidents or hazards on a roadway, turn-signal lamps may be flashed as warning lights while the vehicle is approaching, overtaking, or passing the accident or hazard."

Q Is there any reason that Santa Clara County has the light at San Tomas Expressway and Williams Road set so differently from others on San Tomas? You can breeze from 101 past El Camino, Stevens Creek Boulevard and Saratoga Avenue with minimal delays.

But get to Williams and traffic stops quicker than a college student at a keg party. There are times when it backs up to almost Moorpark.

Ken Geiszler

Campbell

A This is intentional. Signals from 101 to Moorpark run at a faster cycle to handle more traffic in that stretch, while signals from Williams to Highway 17 run slower because there are fewer cars in that stretch. The Williams light is designed to slow traffic between the two sections.

Q The work on Central Expressway between Mathilda and Fair Oaks has narrowed the once luxurious bike lane to a harrowing tightrope easterly ride. There may be a foot of asphalt between the new white line and the edge of the gutter. Please tell me this is not permanent.

Crist Clark

A This is temporary. The county is adding an auxiliary lane between Mathilda and Fair Oaks and the shoulder has been temporarily narrowed during construction. Work should end by Christmas.

Q Here's perhaps the best Apple traffic fix yet. Maybe Apple should lift an idea from the classic movie "The Great Escape" and do as another famous Steve (McQueen) did: Build a tunnel and use it to get in and out of the campus unnoticed. It could lead from the Core to the Caltrain station in Sunnyvale and affectionately become know as The Wormhole!

Jim Donofrio

Cupertino

A Works for me!

Look for Gary Richards at Facebook.com/mr.roadshow or contact him at mrroadshow@mercurynews.com or 408-920-5335.