Evidence suggests otherwise (http://www.iihs.org/research/fatality.aspx?topicName=Overvie...).

[0] "Speeding was defined to include crashes in which the driver was issued a traffic citation for speeding or in which driver-related factors coded indicated speed as a factor (driving too fast for conditions, racing, or exceeding the posted speed limit)."

That's indeed a problem with the statistics, as is their conflation of exceeding a posted limit with driving too fast for conditions. These kinds of games are played all the time -- for instance, consider how an "alcohol related accident" is considered by some authorities to be one in which anyone including passengers in any involved vehicle were over the BAC limit.

The resulting biased statistics make it hard to get the straight story on what factors genuinely affect traffic safety and what factors are overhyped for other purposes.

In this case, it's probably worth keeping in mind how profitable insurance surcharges for speeding tickets are for the companies that sponsor the IIHS.