I read through that 1st article. They do the same sleazy tricks that other researchers do when they are using scare tactics. FIRST, They only report risks and not benefits. Life is all about balancing the risk and benefit. If bungee jumping offered no thrill, people would not increase their risk and do it. Riding free offers tremendous benefit to those who choose it. Lighter head, wind, photo oops, coolness, ease, whatever the rider wants to call it.
SECOND. They report fatalities without reference to NON - fatalities. Helmet or no helmet, riding a motorcycle in Michigan is extremely safe. Roughly 98.5% of registered riders just ride on their merry way. 1.5% or so give up the ghost. Those are great odds. I'll take a 1.5% risk of death for the benefit of riding. So Hemet use may change that 1.5% risk to only 1.49% or whatever but it's trivial compared to the near 99%of riders who don't meet Mr Mahem.