QUOTE (Balta1701 @ Aug 3, 2012 -> 09:14 PM)
And that's a slogan in there for how it sounds to the public, not an actual estimate of the likelihood of failure.
Technically there has to be some margin for error since 2 centimeters would make no difference, if that's how it was considered.
Yeah, NASA stuff is low factor-of-safety because they spend a huge amount of time validating everything so that they can keep the weight down, but it still isn't zero.