Chrome is fastest, that's always been Google's push.. But where it has simplicity it lacks in flexibility.. You can't usually have both simplicity and flexibility because to have flexibility you have to add conditional code everywhere in the design. Conditional code is like this
if ( object is type "picture") view picture
else if (object is type "audio" play audio
Those are conditionals.. The more of these statements you have the slower the code because it has to determine what is being looked at before it is displayed. Also if the browser's code is not well threaded (meaning it doesn't make use of multi-core CPU's) then it will process a page more slowly. How the page is parsed as it is being displayed could have an effect.. But I think how Google does it mainly is to cache the web content at their co-location facilities that exist in every city in the USA, and they regurgitate pages to the web browser if the content hasn't changed since the last access.. This means that any dynamic content will still take a time to load, like a third-party web 2.0 app that always dynamically generates content, content that will never be the same, therefore rendering the use of a cache as useless..
You've probably seen this site called "Akamai"? That's a network based content cache. Optimization comes in different forms:
- compression of content before delivery
- web server caching
- internet based content caches (google, akamai)
- browser based caching
Caching is used inside the computer itself, you have caching in the CPU, caching on the drive, caching in the memory. Caching is like going to the convenience store to get something you need rather than going to the grocery store. But if you need something special, you likely won't find it at the convenience store so you must go to the grocery store.. The only difference, is that here you make the trip when the nature of the content is known to be dynamic. Another method might be to do something like a CRC check on the data to verify with the server that the response to input by the user hasn't changed and that the contents in the user's resident cache are accurate..
You've probably seen those plugins that claim to make your browser go faster? That's all just compression and caching optimizations, if the content being delivered is binary and already compressed, caching is the only benefit such software could offer. But nothing changes about your line speed.