Russ Allbery said:
The alternative proposal is that leap seconds be declared twenty years in advance ... Is that actually possible? Well, sure, provided that we're okay with twenty years of drift. It increases the divergence between UTC and the physical phenomenon that it's intended to mirror, of course, but it bounds that divergence at about thirty or forty years worth of divergence (assuming that we'll continue to use the current low rate of changes) instead of six to twelve months of divergence. Given the low rate of divergence currently, this doesn't seem like a big deal. Having noon be 20 seconds, or even a minute, off true value doesn't seem like it would be too horrible. Or at least the article in ACM was fairly convincing.
The first problem is that there's various things around which assume that the divergence will remain under a second. Nobody knows how many of them will break and how important that is. The second, longer-term problem is that the rate we need leap seconds is increasing quadratically. That makes keeping within that 1 second bound ever harder to predict. -- Clive D.W. Feather | If you lie to the compiler, Email: clive@davros.org | it will get its revenge. Web: http://www.davros.org | - Henry Spencer Mobile: +44 7973 377646