I am glad you are an expert. However, it would be nice if you could also have a less dismissive attitude toward other people when they ask questions or point out discrepancies. I have stated that I think it would be useful to look at factors on helmet efficacy such as hair type, including hair other than Caucasian hair. You immediately questioned where Caucasian was mentioned in the articles that you cited. When I pointed out one place where the authors explicitly mentioned that the use of Caucasian hair was a limitation of their study, you didnāt even acknowledge that but just pointed that the other article didnāt refer to hair type. When I pointed out that study used a wig of straight brown hair that certainly appeared Caucasian, you again didnāt acknowledge the point but focused on the color of the hair when obviously it is hair texture/thickness that would be an important factor. When I questioned your statement that hair type was too variable to be considered in comparative evaluations, you accused me of logical fallacies.
So, yes, you may be an expert, but the way that you engage in the discussion doesnāt really inspire me to blindly trust everything you say.
I have never said that hair up has no effect on safety. I have simply pointed out that the studies you have cited in this discussion do not actually address the issue of hair up at all. I have also said that I think there would be value in doing studies with more real world conditions related to hair types. But since there is no point in trying to have a discussion with you, I will stop attempting it.