There is a critical flaw in this technique: unless you adjust the mirrors each time, it’s too easy for a mirror to shift without your knowledge.
That said, motorcycles can easily move right into a spot that you will not see with your mirrors no matter how you adjust them. That’s just simple physics.
Finally, as someone who’s been nearly sideswiped several times by people relying on your technique: turn your goddamn head.
In fact, if you can’t turn your head, you shouldn’t be driving.
Mirrors can shift no matter how they are set. How is this more of a problem with this technique?
I’ve watched for motorcycles, and have never seen one completely disappear from both mirrors. Please provide a cite or demonstration of the physics you claim makes this possible.
FYI, I rode motorcycles for 25+ years. I’ve nearly been sideswiped, too. But I’d like to know how you know that those occasions were because the driver was using this technique, and not simply being oblivious, like most cagers. The fact you didn’t see them turn their heads doesn’t mean they were using this mirror setting.
Frankly, I’m not convinced that the head twitch technique hasn’t caused as many or more sideswipes because of the factor mentioned above: people unconsciously swerving in the direction they’re looking.
Have you tried the mirror technique yourself? Are you against it per se, or do you believe people should turn their heads as well?
I agree: if you have a disability that prevents you from turning your head, you shouldn’t be driving.
I’d rather smile with the knowledge that I have initiated one more enlightened person to the One True Way of Mirrors. 
But seriously: have you tried it, or are you really just rejecting it out of hand?
I think a lot of people are just fixed in habits they learned when they were teenagers and, despite recognizing their drawbacks, are afraid or unwilling even to consider an alternative. I expect this from the Teeming Masses, but not so much from my fellow Dopers.
If you’re worried you’ll have an accident, make a point at first of driving somewhere you know the traffic will be light. And give it a fair chance. You can keep twisting your head, if you want, and you can always go back to the (bad) old way if you really don’t like it.
BTW, I’m not arguing against the head twitch in all circumstances. With mirrors adjusted the “bad” way, it is necessary almost all the time. With them adjusted the “good” way it is not as necessary, but as long as you aren’t swerving when you do it, it doesn’t generally hurt.
My real concern is that I would get out of the well-drilled habit of always looking and then cause an accident one day if the mirrors happened to get bumped out of alignment and I was trusting them to show everything.
I have. I find it hard enough to interpret the information with no sense of where I am that I settled on a compromise. If I lean just barely to the side, I can see the side of my car in the mirror.
I haven’t swerved while turning my head since I was a teenager. The only problem with the head swivel, imo, is that you might be distracted from looking ahead.
Oh, and I share a car with my husband. I adjust the mirrors almost every time I sit in the driver’s seat. Takes a moment, but it’s certainly no big deal.
If the mirrors shift while in motion the driver has no frame of reference for what is correct and is tootling along secure in the ignorance that they are seeing everything.
It’s called a lane change.
Assume you’re in lane 1. Rider comes up in lane 3 (or 4) and changes into lane two as they are even with you. They may or may not be in a position to dominate the lane.
Unless the mirrors on your car are even with your front wheels, this rider will not appear in your field of view. They may appear in your peripheral vision, but there is no guarantee.
That’s why your technique is dangerous. It relies on the assumption that everything is perfect, but the only way to find out something is flawed is to hit another vehicle or – more likely – to cause a crash behind you as drivers brake and dodge out of your way.
It’s easy enough to tell if the mirrors are in the wrong position.
That applies to cars as well. The mirror positioning described above doesn’t account for the lane two across from yours and you will need to check by turning your head in these circumstances. That’s not a flaw in the system.
It’s only dangerous if you assume you can see literally everything in the mirrors. I don’t see anyone suggesting that.
You seem to be suggesting that because one mirror setup has flaws, then we should use the even more flawed setup. Shouldn’t we be using the setup that minimises blindspots?
The key to not hitting other vehicles is to, a, know that they’re there in the first place (i.e., when it comes time to change lanes you know all the cars and bikes that are around you and you just need to confirm their positions), and b, specifically look for hard-to-see vehicles. E.g., when turning right, look in your right side mirror, and say to yourself, “any bicycles coming up the inside?”
I position my side mirrors out for proper field of view, but it does put the angle of the mirror quite off kilter from the housing, almost to the point I can see the guts behind. Car designers are definitely assuming that most people angle them in too far (to see the side of the vehicle), so the proper positioning looks bad as a result.
There’s the these features on many newer cars called blind spot warning signals, that indicates when there is another vehicle in your blind spot.
Thanks to Richard Pearse for his excellent reply.
I’ll reiterate the point that neither I nor anyone else promoting the right way of mirror adjustment is claiming that it will show everything you need to see all the time without moving your head, or that drivers don’t need to have proper situational awareness at all times. As I said, I rode motorcycles for 25 years, and I also taught High Performance Driver’s Ed for about eight years. So I know very well about the need to be fully aware of your surroundings when operating a vehicle at high speeds. I’ve never suggested that such awareness wasn’t extremely important.
I don’t blame Barbarian for being annoyed at oblivious drivers. But there’s no necessary connection between obliviousness and mirror adjustment, except that the bad technique, by hiding things you would otherwise see in your mirrors, makes you more, not less, oblivious.
As Richard Pearse said, the standard (bad) way that most people use is far worse than the good way we are suggesting. No one claims that it’s perfect, or that it can show you a 360-degree view of everything around, under, and above your car, or that you’ll be able to drive without even looking out through the windshield, or that it will correct your poor eyesight. Only that you don’t have to have the blind spots **that you create **when you turn the mirrors in too far.
Although I don’t much care about the esthetics, this is a real problem that I have encountered on some cars: the proper position is just at, or even slightly beyond the mirrors’ limit of adjustment. In a few cases, I’ve been in cars where I couldn’t turn them out as far as I needed for the proper view. Very annoying.
I’ve only had one or two rental cars with this feature, but I was amused to note that, with my mirrors adjusted the good way, I could see cars coming up in the “blind spot” well before the little light warned me about them. So the high-tech “solution” to an unnecessary problem was worse than simply adjusting the mirrors the right way.
Here’s an interesting factoid: although the rear view mirror for cars was patented in 1921 by Elmer C.A. Berger, the first recorded use of one was in 1911 by a guy named Ray Harroun, who put it on the car he used to win the first Indianapolis 500. No other race cars had them; instead they all had “riding mechanics” who sat next to the driver and, among other duties, told him what was happening around them.
After reading this thread I have become more conscious of how the world looks through my mirrors. Rather than just using them, I am now thinking about what I see and how it works. (Recall that I position my mirrors using the “Car Talk” method, which is what they also teach in my county’s Driver’s Ed program, where the view in the side mirrors slightly overlaps the center mirror, rather than sighting them along the side of the car leaving large blind spots.)
I found that there is no object that can be hidden by the C pillar, except maybe if a bicycle were drafting my right rear bumper (a scenario I have not tested). I have a continuous view and a motorcycle that would be in the next lane and behind the C pillar and not seen in the center mirror is clearly visible in the side mirror.
Precisely. This is the point so many people miss. The areas around your car that not visible with the proper mirror settings are so small and restricted that it is difficult to imagine a vehicle “hiding” in them in normal circumstances.
Although I haven’t tried it, I suspect that a person standing right next to the rear corner of the car might not be visible in either mirror, but no motorized vehicle is that small or could hold that position in traffic.
A convertible with the top down/roadster with a NASCAR-style panoramic rearview mirror would not have blind spots …but there’s those pesky laws about rollover and side-impact protection and such. modern car have such high beltlines and tiny windows because they’re required to not crumple into a ball in a crash.
Two words: transparent aluminum
Coupled with several eyes around the back & sides of your head you’d have something. Absent that, transparent aluminum get you nothing. Nothing but whales that is. 
My view is I run my mirrors along the sides of my car. They’re for gauging the closure rate of nearby cars 20-100 feet back in the adjacent lanes. As to cars up close & alongside, that’s why your head is mounted on a swivel. Use it as intended.
I suspect half the people that pull in front of me when I’m closing at 30 mph are using their mirrors the “good” way to cover their blind spots alongside. That’s not what they’re for people.
Why duplicate in your side mirrors what you can see in your rearview mirror? Especially at the cost of creating blind spots that aren’t necessary?
Wait, you’re going 30 mph faster than traffic around you? In your car, not in a plane? I don’t think people setting their mirrors the “good” way are the problem in this situation!
Says who?
Maybe I read the OP too simplistic.
The answer is trade offs. A larger mirror, combination mirrors or sensors/cameras are all feasible options. All will add to the cost, style or weight of the car.
A cargo truck convex mirror would easily eliminate blind spots. Do you want that on your mini-Cooper?
