Yeah, for a website with 2 seconds or more load time, instantclick will probably only help remove 100-200ms. Still worth it, but not a huge improvement. There will be lower hanging fruit.

Where this library shines is if you already have a decent, fast-ish website with ~500ms load times. This can bridge that final gap and make it look like the whole site is loading in a flash. Amazing to see in practice. It's more the fact that the page layout can be computed before the page changes. it makes a huge difference in perception.