http://www.sltrib.com/utah/ci_3640893
"Though he was wearing a bike helmet, Corliss reportedly suffered severe head trauma as a result of the accident." Apparently Corliss was a marketing manager for Bell as well.
Of course the answer is always the same - "A helmet can't save everyone". Of course the mortality figures before and after helmets haven't changed.
"... it is impossible to build a helmet that will offer significant impact protection" Dr. George Shively, The Snell Memorial Foundation
"... helmets will mitigate the effects of falling off your bicycle and striking your head... If a cyclist is accelerated by a car, then the helmet will not work and will not prevent a severe or even fatal injury" Dr. Michael Schwartz, neurosurgeon and member of Canadian Standards Association Committee establishing helmet standards
http://www.magma.ca/~ocbc/hfaq.html
http://www.magma.ca/~ocbc/kunich.html
http://www.magma.ca/~ocbc/fatals.html
http://www.helmets.org/veloaust.htm
The fact is that a helmet was designed to do one small job - to mitigate a fall with no other complicating factors such as collisions with anything else. If you fall and hit your head on a curb - goodbye. If you fall and hit your head on a stopped car thereby adding your forward motion to the energy the helmet needs to absorb - goodbye. If you're hit by a car - goodbye.
Of course in ALL of these cases you might luck out. And in JUST falling down you can exceed the capacity of your helmet to protect your head as well.
DO NOT FALL DOWN AND HIT YOUR HEAD. IF YOU FALL ALWAYS PROTECT YOUR HEAD.
If you think that you're going to get away any other way you're just being silly.