Yeah, sadness >>> anger regarding the whole thing.
That said, I don't think ANYONE understood the effects of stuff like this ten years ago, we barely are starting to get it now, and it's how so many people over the past 30 years had things like this happen, from NFL players from Mike Webster to Justin Strelzyk
http://en.wikipedia.org/wiki/Justin_Strzelczyk to Junior Seau.
Senseless tragedy, yes, but I don't think anyone's truly to blame for it, any more than anyone's to blame for the effects of things like lead poisoning from old water pipes or something.