and leap seconds in the past aren't erased.

Leap seconds can need to be subtracted, (due to nutation?), though this is likely to occur much less frequently than their being added. It also doesn't detract from your quoted point, but does complicate things a little.

I also read(search for IERS) that leap seconds are only added on June 31st30th or December 31st, so bi-annual updates should suffice.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re^3: Leap Second by BrowserUk
in thread Leap Second by esskar

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