A very poor analogy. You never deliberately initiate a collision in a car. Also being surrounded by a car body gives you a false sense of invulnerability.

That may not be far from the truth. It may be akin to the counter-intuitive removal of signs and signals from roads to increase safety:

http://www.wired.com/wired/archive/12.12/traffic.html

I think that the primary logic of the article is that helmets were designed to prevent skull fractures but an unintended outcome is an increase in concussions.

Actually, there is a body of research attesting to your logic:

http://www.econtalk.org/archives/2006/11/peltzman_on_reg.htm...

I believe some studies have shown that removing traffic control devices can actually reduce accident rates by forcing drivers to be more aware of traffic around them and make accommodations.

In theory you're right, but probably not so in practice. Football players would see the consequences of the change much more quickly - they'd go from being able to dive at a player head first and have a cushioned impact to having their skull connect with something hard and feeling a lot of pain. I'd expect their behaviour would adapt in response to that. Similarly car drivers probably wouldn't drive any more safely until they experienced the consequences of crashing while not wearing a seat belt.

Make cars out of glass and put spikes on the dash and you'd see different results.