I'm just arguing for riding lawfully. That seems to be quite controversial, now I understand why there are so many cyclists riding dangerously. If we were to do that maths would it be personally safer to wear a helmet and run red lights or to go without a helmet and wait for the lights to turn green. Then we could ask which is safer for other road users.
Data from the Idaho stop laws indicate that it is safer treating red lights like stop signs (Stopping and then proceeding through the red light when clear).
So your answer is, it is safer to run red lights with or without a helmet.
I don't wear a helmet...it's a personal choice...but I do have front and rear lights and follow the rules of the road, stopping at red lights, signaling and taking the lane firmly etc.
It annoys me that I see so many other cyclists on my urban commute that faithfully wear their helmets and then proceed to ride so dangerously, going through red lights
and cycling up on the inside of trucks and buses. People seem to equate helmets with personal safety rather than how they ride or whether they have lights at night.
This alone is helmet thread fodder. Feel free to discuss your views there in the future.