According to https://github.com/ampproject/amphtml/blob/master/builtins/amp-ad.md https://github.com/ampproject/amphtml/blob/master/builtins/a..., ads are injec

According to https://github.com/ampproject/amphtml/blob/master/builtins/amp-ad.md https://github.com/ampproject/amphtml/blob/master/builtins/a..., ads are injected as an iframe: "Ads are loaded like all other resources in AMP documents, with a special custom element called <amp-ad>. No ad network provided JavaScript is allowed to run inside the AMP document. Instead the AMP runtime loads an iframe from a different origin (via iframe sandbox) as the AMP document and executes the ad network’s JS inside that iframe sandbox." While I agree that many current ad scripts prevent websites from fast page loads, I don't really see the difference here (unless the actual ad network JS is modified to be faster, too - but then again, why do I need AMP for this?).