This is not a good idea because it breaks years (decades?) of expected behaviour on desktops. When a user scrolls a page back to the top, the expectation is that they'll see the top of the current page from the most recent pageload. With this, there's no way to revisit the top of the page in its current state and it's just gone when you scroll back to the top. This doesn't save much time/effort as a refresh is a comm…
In the best touchscreen implementations, you have to overscroll past the top by a certain amount to get the reload behavior. Further, while overscrolling less than the threshold amount, you get a visual hint that further pulling will reload, while letting go will avoid a reload. This Hook.js implementation doesn't yet seem to have that level of refinement... but if it could, I don't think the user expectations or con…
Touch is different, because you continue receiving touchmove events even if the page is scrolled to the top and the touchmove events don't have any visible effect.