Was looking at this in the past, a couple of thoughts. 1. Some articles seem to indicate that repetitive impacts as small as 10g may have cumulative effect. By increasing the effective diameter of the skull, helmets may increase thr likelihood of impact by reducing the necessary angular displacement for the head ro collide with back of seat. As materials of many helmets are tuned for more severe impacts, they may not offer meaningful protection in this domain. 2. Do helmets reduce peripheral vision?
The Crasche hat does not reduce peripheral vision. You can't see it (without a mirror) when it's on your head. The hat is very thin, and the protective material has rubber on the side facing your head and something very strong on the other. You raise valid objections to wearing normal helmets while driving.
A 2006 study showed that “280,000 people in the U.S. receive a motor vehicle induced traumatic brain injury every year” so you would think that wearing a helmet while driving would be commonplace. Race car drivers wear helmets. But since almost no one wears a helmet while driving a regular car, you probably fear that if you wore one you would look silly, attract the notice of the police for driving while weird, or the attention of another driver who took your safety attire as a challenge. (Car drivers are more likely to hit bicyclists who wear helmets.)
The $30+shipping Crasche hat is designed for people who should wear a helmet but don’t. It looks like a ski cap, but contains concealed lightweight protective material. People who have signed up for cryonics, such as myself, would get an especially high expected benefit from using a driving helmet because we very much want our brains to “survive” even a “fatal” crash. I have been using a Crasche hat for about a week.