Especially the toolbar but the point is valid for the entire site, why the broswer has to reload the whole page when it can to replace the content section of the page with the only new content. 

Very much content on the site is static and does not change. I do not see the logic of always making requests to the server for the same content that has not changed at all. 

EXEMPLE: In the discussion forum, browsing is done quickly between menus because reloading is done only for the new content and not the entire site.

But there are many sections of the site where navigation experience is totally unpleasant.  For example, if you are browsing the MARKET menus every time you click on a menu, there seems to be a quake over the market title that is missing little and crashing over you. already my eyes hurt

It does not look like a professional site at all.

If I were to be an environmentalist I would say that such a change would reduce the carbon footprint. But I am a manager and I think more about the money thrown out of the window by the whole community. And I think even more about the user experience, which translates into a slower navigation than is possible with the technology we have at our disposal.