[wmf]

You know in some places they will forget the conversion so you'll have weird cases that are off by 37 seconds.

[kqr]

Surely that's

a) Discovered sooner than a leap year bug, and b) Given that humans and not machines are the consumers of the UTC time, less consequential than a leap year bug.

[saurik]

That seems like it would be obvious, though, so people would fix it.