I've got Google ads on my blog and they add 2.4s to a 4.9s load time. Google's own Pagespeed shows me that they [Google] are not doing basic things like caching immutable resources or minifying javascripts - which to me is really baffling.

Indeed the longest events on the page - as reported by Firefox dev tools - are connections to https://tpc.googlesyndication.com/ which are 0.7 and 0.8s; connection to https://www.google.com/pagead/drt/ui which is 1.3s; and connection to http://fls-eu.amazon-adsystem.com/ is 1.4s.

Meanwhile on a commercial page I manage the second hint on my 94/100 score on Pagespeed is to "leverage browser caching" - all the resources listed, like api.js, are part of Google's analytics. Under minify javascript there are Facebook and Google resources (for Like and +1 buttons).

This is of course not a scientific analysis; instead I say it to illustrate that the smart people at Google and Facebook don't appear to be focussed on this end of things - I'm guessing the minify thing saves them resources, that they minify based on a balance of delivery costs vs. processing costs and that full minification is not worthwhile to them ... I'm just annoyed I can't get a 100/100 pagespeed score without removing Google's ads/analytics from pages!