I don't know Gabe, I think a lot goes into the computation of how well a helmet protects. A direct hit against a solid object or a glancing hit? Rotational force? Multiple low velocity hits vs one higher velocity hit? Totally correct fit of the helmet or on the loose side? New helmet or 10 year old helmet?
A bunch of variables, many almost impossible to measure in the real world.
I don't take exception with your point that the motorcycle sport is dangerous, and doesn't forgive really stupid moves. It shares that with other active motion sports as well as aerobatics and perhaps ocean sailing.
And I do think that first tier helmet manufacturers are studying data (I'm thinking recent football concussion studies) and makers like 6D and Bell with their attempts to reduce the velocity of impact, or Arai with attempts to make a helmet slide rather than "catch" are doing the best they can ... and therefore deserve our support over $100 Walmart specials.
For sure I get your point. But there's a line that gear-snobbery crosses when it discourages new and/or casual riders from wearing protective gear of any kind, which is what happens when folks hear stupid bullshit like "wear a $10 helmet if you have a $10 head," as if a cheap helmet is worse than nothing. It's not.
In fact, it's scientifically proven that a $50 DOT helmet prevents brain injury pretty much as well as a $500 Snell. But yeah--if you can afford it, by all means support the established brands that lead the way in engineering. But some of the so-called "premium" brands have their helmets made in the same generic, state-owned Chinese factories where Walmart makes theirs.
I welcome the flood of cheap gear on Amazon, as a rider can get kitted up for less than $150 head to toe with stuff that's probably better then the top-dollar stuff from 20 years ago. And 20 years ago that same rider would be wearing a spray-painted 1980 Bell Star, shorts and sneakers.
As for my original contention that that helmet will protect you from 15-20 mph of impact with a solid object, well, you can nit-pick it all you want. Just remember that the helmet gets dropped on the headform in the DOT tests from what--8 feet? 10 feet? That's about 12 mph I think. 20 mph would be 20 feet (ish), 30 mph 30 feet, and 40 mph 40 feet--a 4-story building. Your helmet would have to be a yard across and you'd look like Gazoo from Flintstones.
One thing that irritates me about Internet discussions (so why do you do them, Gabe, why? I don't know.) is when the geeky engineering types try to bury your point with an endless litany of very technical arguments. Sure, all those factors matter, but how much? Ten percent? Five? .5? I'm not saying this isn't important.
I've done a few stories about helmet testing and I talked to helmet designers and engineers from Snell and elsewhere. I know it's complex and it's all a very complex balancing act. I don't doubt everybody involved has the safety of the rider in mind first and foremost, snarky, cynical comments about "they just want to make money" nothwithstanding. But still, if you hit your head on a stopped object and your head is going faster than 20 mph, you'll probably die or be better off dead, whether a glancing blow or rotational blow or angular bilateral-axial traversement gyroscopic inertial paramoment or whatever jargon you want to spin at this. Your brain is going to bruise and swell and likely be damaged unless you're in front of a brain surgeon in 30 minutes.
Please try to see my point: no matter what kind of design, materials, quality, innovation, etc, the basic fact is that 1.5 inches of Styrofoam can only do so much. Which is not much.
We need to stop implying that helmets make us 'safe.'
