Units of measurement matter

OK, by now it should be obvious that the country (or at least the AP’s journalists) have a quantitative literacy problem:

The tests were conducted at 40 miles per hour (17 kilometers per liter), representing a severe crash.

Did I miss the memo equating speed and gas mileage?

Tip from Language Log, where the commenters run amok with off-the-wall conversions.  Check it out.