Let's be careful out there, people!

When a [driving] situation feels dangerous to you, it's probably more safe than you know; when a situation feels safe, that is precisely when you should feel on guard. Most crashes, after all, happen on dry roads, on clear, sunny days, to sober drivers.

Tom Vanderbilt, Traffic,
reviewed by Jonathan Yardley in today's Book World

Update: If the quotation is representative, Mr. Vanderbilt was ill-served by his editor. That first sentence should read: "When a [driving] situation feels dangerous to you, it's probably more safe safer than you know; when a situation feels safe, that is precisely when you should feel be on guard." (You won't be surprised to learn, I'm sure, that Yardley didn't deign to comment on the quality of Mr. Vanderbilt's prose.)