It's hard to see this being much of an impact, even for stressed sites with a lot of Chrome users; people don't usually sit there mashing the refresh button when their page won't load. Most folk will actually implement their own"back-off" feature, Sure, there are outliers, but this is a game of big numbers and average statistics.
Where this can help is with automated page loading. Your saved session has twenty tabs with pages from a single site? That's all loaded at once, in parallel in the browsers I know about. I imagine it can be a considerable load in some cases.