The problem isn't in hardware or drivers. It's in Windows and the application ecosystem. Even though Windows WM_MOUSEWHEEL allegedly supports fine-grained control, in practice it isn't implemented anywhere, not by vendors, not by applications.
(That is, I think you missed my point. The reason Apple's support is good is not because it's multi-touch; it's because it's continuous. It's also multi-touch in Windows using the Bootcamp driver - my MacBook Air spends most of its time running Windows - but it is still discrete.)
(That is, I think you missed my point. The reason Apple's support is good is not because it's multi-touch; it's because it's continuous. It's also multi-touch in Windows using the Bootcamp driver - my MacBook Air spends most of its time running Windows - but it is still discrete.)