Don't know the scholarship behind the "street forum" comment you read, drsprocket, but . . . the conclusion (i.e., full-face helmets pose additional injury hazards) is contradicted in the Hurt Report
, the first large-scale scientific analysis of motorcycle injuries.
From a summary of findings from about one thousand (IIRC) motorcycle accident investigations:
52. There is no liability for neck injury by wearing a safety helmet; helmeted riders had less neck injuries than unhelmeted riders. Only four minor injuries were attributable to helmet use, and in each case the helmet prevented possible critical or fatal head injury.
I'll stick in this one, just for good measure:
48. Safety helmet use caused no attenuation of critical traffic sounds, no limitation of precrash visual field, and no fatigue or loss of attention; no element of accident causation was related to helmet use.
The research was published by Hugh Harrison Hurt, a professor at the University of Southern California, who later founded the "Head Protection Research Laboratory." The design and manufacture of the energy-absorbing helmet you wear today sprang from the research of Hurt and others.
Hurt was inducted into the American Motorcyclist Association Hall of Fame, years shortly before his death.
Again, I don't know the scholarship behind the street forum, but--I am personally familiar with Professor Hurt's technical competence and diligence, profoundly trusted by me.