Improve caching a bit more about specref HOT 4 OPEN

Can you explain what that would change?

from specref.

Sending both Expires and Cache-Control: max-age shouldn't be necessary unless you intend to target old HTTP/1.0 clients. You can drop the former.

My understanding is that if you have an ETag then you can use expiration dates farther in the future, because the client will use If-Match to which you can respond with a 304, whereas after the expiration time it will make an unconditional request (disclaimer: I'm no expert on this, it's just my understanding). Obviously this is only useful if you handle the conditions.

from specref.

Oh, so we hit the server everytime no matter what?

from specref.

You're probably not going to hit the server every time. But sometimes you are. The behaviour on reload for instance (and spec dev is all about the reloads) is browser-dependent. You're going to get If-Match requests after the cache expiration time too; it's not a bad idea to honour them if it's cheap enough for you.

from specref.