There is a difference between
obnoxious and
audible. They need not be the same but there is overlap. Again, more in the video.
It's also a category-error to compare 'good riding' to 'loud pipes' or 'audible pipes'. Good riding is a given, all the time. On top of that we strive to be visible
and audible because on-balance, that's superior to NOT being visible or audible, or being less visible/audible. See?
Humans and most mammals notice sounds. We hear because individuals literally survived better for being able to hear. Evolution selected for this trait. Why ignore it when it comes to cagers being able to sense your presence in any way they can sense anything? This is why large vehicles have back-up beepers, or why emergency vehicles have sirens, cops have loudspeakers or bullhorns and nearly every manufacturer-created and street-legal vehicle in the world comes with a horn (which is intended to be
heard). Some electric cars have been deemed higher-risk for children and animals in residential neighborhoods, along with other motorists, so some have been fitted with artificial noisemakers simply to make people aware of their presence through a sonic medium.
Passive noisemakers of reasonable volume (exhaust and other noise) helps some creatures self-select to preempt your arrival and get out of the way. If kids are playing in the street in a residential neighborhood with vision blocked by cars and hear you coming, they can respond before you get there. Same with small animals and such. Parents can scoop up kids before they dart in to the street because they heard you coming.
Good riding is a given. We all should strive for this. Being visible? A given. Being seen is better than not being seen, in any way you care to be seen (high-viz, good lights, contrast, large swaths of color for a better silhouette, etc.). Likewise, being audible is simply another way for the cager to know that you are there and that you are on a bike (even the type of bike is indicated by sound). It is never the case that sound is said to work perfectly in all cases. Why? People have other distractions.
What is a common refrain from cagers when they fail to yield to a motorcyclist, resulting in an accident? 'I didn't see him', and these are people who are required to pass eye-exams in order to drive. Why then do we keep trying to be seen? It's because sight is reliable enough to trust that person not to rear-end you at the stops, unless they indicate that they're distracted or haven't noticed you in time. In fact, the squealing of brakes is an AUDIBLE signal that someone is about to rear-end you if it's coming from behind.
It's a fallacy to assume that loud pipes means you don't have to also be a good, astute or observant rider. Does wearing hi-viz gear mean you should ride like crap? No. If loud pipes don't save lives, then loud
colors don't save lives—except that they can and do. Neither sight nor hearing works perfectly because humans are imperfect, but that's why more stimulus>less stimulus.
Snipers wear camouflage for a reason, and they lie still for a reason. They do this to avoid detection. Thieves sneaking around at night may attempt to be both less visible AND less audible. So, why when it comes to being noticed by errant cagers would we not want to exploit both visual AND audio stimulus?
And that is the crux of the argument. Loud pipes save lives, and the statement is true even if it only saves your life once.
-Taken from the comments of the original video. Sounds reasonable to me. Yay.. 1 star thread..

my *feelings*