If WPT says a given webpage is blocked on CPU, what are reasonable next steps to mitigate the problem?
For example, Huffington Post (http://www.webpagetest.org/result/141021_2V_1709/1/details/)seems to be that case where the first resource optimization would be to fix the CPU
same for this site called www.thredup.com(http://www.webpagetest.org/result/141021_1E_170W/details)
I can guess it might be to profile them under chrome timeline , figure out the culprit., etc
If you turn on timeline capture then you can get an idea for what it is doing and if there are expensive operations. Make sure to run several tests though and make sure it is consistent.
Also, running at “Native” speed is going to drive things to be more CPU-limited than the slower bandwidths.
Generally if the browser is getting resources fast enough then it is always going to be CPU-limited (though it could still be spending a lot of time doing image decoding, layout, js execution, etc).