I really suggest you look here: https://channel9.msdn.com/Shows/Going+Deep/Lars-Bak-and-Steve-Lucco-Chakra-V8-JavaScript-Open-Source https://channel9.msdn.com/S

I really suggest you look here: https://channel9.msdn.com/Shows/Going+Deep/Lars-Bak-and-Steve-Lucco-Chakra-V8-JavaScript-Open-Source https://channel9.msdn.com/Shows/Going+Deep/Lars-Bak-and-Stev... They do talk about the chicken and egg situation, where top sites will optimize for engines, then engines optimize for sites... i.e. it highly depends on the sites - of course all browsers test on top sites and optimize for them. But then the cycle repeats.