Antonio,
The summary article, written in 2000 or 2001 IIRC, is archived at the newspaper's web site. You must purchase access to it. We have a hardcopy somewhere, but the numbers you mention sound about right.
The most recent article is
here, but only mentions the 2005 data in passing. Someone, somewhere has assembled a database of the Observer's data and posted it online. Unfortunately, the bookmark has been lost on our end and the search engines aren't being very helpful. Perhaps the site is down.
Road racers are less than 10% of racers by headcount, and most of the injuries are found on oval tracks where safety does not rank high on the priority list.
The SCCA's issue is that the problem doesn't go away in road racing, and the numbers stay fairly consistent: ~20 deaths per year X half of fatal injuries are H&N injuries = 10 H&N fatalities/year. The statistics imply that a road racer is going to suffer one of these injuries every year (I can think of two in the past four months), and I'm sure the Club is not eager to go to court every year and tell a jury that H&N restraints are unproven and too expensive.
And that gets to the practical problem. In order to protect from frontal and side impacts to the level seen in pro racing a driver is going to need to drop ~$1K on a H&N restraint and ~$1-$2K on a seat
if an "SFI certified" H&N restraint is mandated. If you tell budget racers they must spend $2-$3K on safety gear so one life can be saved you will start a stampede out the door. This isn't a simple decision for the club.
On the other hand, if we get the thumbs up from Topeka to demonstrate performance and skip the SFI sticker, we'll test the $295 Link model at Delphi. If it works--and we are 90% confident it will--the driver will then have a choice: $3,000 or $300.