> Long term, who knows. But we would like to be able to do date calculations a couple of years into future.
On the fairly safe assumption that you don't care about being off by a few seconds, leap seconds aren't a factor there. Assuming one leap second every month (!), your computed date two years out will be off by less than half a minute. No one will ever even notice; the entities that consume dates in calendar format -- people -- aren't capable of meeting time tolerances that tight.
If you need to coordinate something down to the millisecond, calendar dates aren't for you.
That's the point, if you need to coordinate things down to the millisecond, leap seconds are incredibly harmful, and if you don't, they are irrelevant.
On the fairly safe assumption that you don't care about being off by a few seconds, leap seconds aren't a factor there. Assuming one leap second every month (!), your computed date two years out will be off by less than half a minute. No one will ever even notice; the entities that consume dates in calendar format -- people -- aren't capable of meeting time tolerances that tight.
If you need to coordinate something down to the millisecond, calendar dates aren't for you.