I would say proper (good quality) helmet is giving you more chances to avoid serious head injurious.

Regarding false sense of security.. it's the same thing as with all security add -ons in your car. Security engineers are frustrated with the fact that their work is not giving better results, because drivers are relaying on ABC, ESP...and other safety features in modern cars and driving faster, breaking later, driving with less safety distance. But that doesn't change the fact that modern cars are much safer then they used to be.

Mipi