According to NASCAR safety consultant John Melvin, an expert on impact injury, seat belts that go over both shoulders would save loads-o-lives if they were installed on passenger cars. Shockingly enough, Melvin believes that NASCAR drivers who wear 5- or 6-point harnesses seem to fare better in high-speed side-impact crashes than they would have if they'd they been wearing the same single-shoulder belts installed in, say, the Blue Max Mercury Topaz. Ford is already researching a seat-back-mounted dual-shoulder belt, which supposedly resembles a pair of suspenders. We're hoping they'll add window nets as well.
Double shoulder belts called safer for drivers [McClatchy]