I'm really not. max-age and the Expires header, properly set, will control caching at just about every possible step. If you refresh apple.com several times, you'll notice the max-age cycles down with each refresh, and the Expires header stays the same. They're obviously set up to cause the page to have a short maximum lifetime in both public and private caches, and in the case of a launch, it's not that hard to make sure that the old copy of the page expires at 11 AM PST or whenever you want your announcement to go live.

Announce product, push deploy button on website, people hit website and browser requests a new copy of the page because its current copy expired at 10:59:59, and presto, it all magically works.