me minimal brain function, I start asking questions:

• “How old are the tires?” I already knew that with my Carolina friend. If this were a five-year-old car I would have theorized that the aging process had reduced grip. A tire is a lot like a human: It can die even if hasn’t gone very far or done very much.

• “What’s the tread depth?” This is a good question because they don’t have the answer. I’ve found that “Quite a lot” usually means “Almost none.” Say, “I’m sorry, I need an exact measurement,” and then make a run for daylight.

• “Have you done a smoky burnout or do you have a teenage boy in the house?” is another good question. With some UHP tires, a smoky burnout will cause the rear tires to radically lose grip. I’ve asked several tire designers: Their best guess is that the burnout overheats the tread, perhaps causing it to re-vulcanize, taking something out of the tread’s performance parameters. Regardless, the tread loses grip. Since the front tires retain their original traction, the car becomes tail-happy in even modestly aggressive driving. The Corvette owner does have a teen boy in the house, but he would NEVER do such a thing. Yeah, right.

• “Did you set the tire pressure to the vehicle manufacturer’s specifications immediately before the drive?” This is a good opportunity for them to lie. It’s also another chance for me to launch into a lecture. I tell them I’d rather have the pressure 3 to 5 psi high than 1 psi low.

I could come up with no obvious diagnosis for the state of the Corvette Grand Sport’s Goodyears. Since the driver was complaining about dry grip on 40F days and clear roads, I wondered if its tread rubber wasn’t borrowed from a race tire.

The Michelins found on the Dodge Viper and Corvette ZR-1 used a tread compound that is very similar to that used on the company’s Pilot Sport Cup club-race tire. Race-compound tread begins to temporarily harden somewhere south of 40F. Later research showed that the Eagle F1 Supercar EMT employs a normal summer tire compound.

Had I known that the speed limit on the Blue Ridge Parkway is never higher than 45 mph, I would have asked the Carolina Corvette how he noticed any loss of grip without radically violating the speed limit.

With the benefit of hindsight, I suspect my questioner was experiencing a loss of lateral firmness caused by inadequate air pressure. To most of those who do not make their living as test drivers, a lack of lateral firmness gives the impression that the tire is about to break traction.

The truth is that the tire has plenty of grip and is far from its limit. However, unless the driver has the confidence to push past this uncomfortable feeling, he’ll swear the car was about to spin out.

Back to the inadequate pressure. I don’t doubt (too much) that the Corvette driver had recently checked his tire pressure. However, it’s likely he’d checked them a) when they were warm, and b) when the ambient temperature was 40F or warmer.

If the outside temperature drops 40F, his tire pressure would have dropped by 4 psi or so. Such a difference could account for the reduction of lateral firmness, yet would not cause the TPMS to illuminate.

By the way, my father often didn’t try to diagnose tennis elbow or an arthritic neck in social settings. He’d say, “Cancer. Inoperable.” That’d end the request for free advice.

May switch my technique to the simpler: “Rust. Terminal. No cure.”