Visual Progress - Dev Tools

[Jeff]

Hey Pat,

It's not clear at all to me how the dev tools speed index and Visual Progress % work for non WebKit browsers, specifically IE. If IE (say IE9 to be specific) doesn't use WebKit, where does the data come from? The algorithm (defined here https://sites.google.com/a/webpagetest.o...int-Events) talks about how it's implemented using WebKit, but doesn't say anything about how it works without for non-WebKit browsers.

Thanks,
Jeff