$ curl -H "If-None-Match: Tue, 10 Jan 2017 12:22:50 GMT" -i https://www.blogger.com/feeds/2297891732714248935/posts/default
HTTP/1.1 200 OK
...
Expires: Tue, 10 Jan 2017 12:30:24 GMT
Date: Tue, 10 Jan 2017 12:30:24 GMT
Cache-Control: private, max-age=0
Last-Modified: Tue, 10 Jan 2017 12:22:50 GMT
...
<?xml version='1.0' encoding='UTF-8'?><?xml-stylesheet href="https://www.blogger.com/styles/atom.css" type="text/css"?><feed xmlns='http://
$ curl -H "If-Modified-Since: Tue, 10 Jan 2017 12:22:50 GMT" -i https://www.blogger.com/feeds/2297891732714248935/posts/default
HTTP/1.1 304 Not Modified
...
Expires: Tue, 10 Jan 2017 12:31:08 GMT
Date: Tue, 10 Jan 2017 12:31:08 GMT
Cache-Control: private, max-age=0
ETag: W/"f00008527fff63e7daa1cc509244814d72b199d78acabd34d6c397188b7a1e94"
Server: GSE
Alt-Svc: quic=":443"; ma=2592000; v="35,34"
And this should be acceptable enough for us to actually make many requests probably.