I’ve performed a simple test: create 2 blank framework pages (of the same framework), and navigate from one to the other, to see which and how much data is loaded from cache, and which amount of data will be loaded each time a new page is opened.
I know this test might not be 100% accurate, but it will give you an estimate how good or bad a framework behaves in real world examples. So beside 100% page speed, you have to look at an overall size of the network traffic for the whole site.
- Foundry 3: 328 kB (looks like if you use bootstrap icons, add 120 kB)
- Foundation 6: 224 kB (if you do not use the RW default to consolidate CSS files, almost 0 kB)
- Source: 15 kB
- Blankstrap: almost 0 kB
Unfortunately RW (or the stacks integration into RW) doesn’t help with creating a site design. At the end, each page is designed for itself, even if you use the same style settings. But you also see that, if developed with this in mind and correctly configured, you’re able to get fast sites with low network traffic (and not only fast pages).
This test should be re-done not with a blank, but with a comparable content rich page.