I'm not a kernel dev, but I've seen this sort of thing before and the kernel almost always picks the spec and assumes the hardware doesn't lie. IDE HDs and if they are done writing, ACPI, hard drive sector size. Of course there are some work-arounds in the kernel the intel FPU bug comes to mind, and i'd bet a fair amount of the ALSA drivers as well.
No announcement yet.
Linux 3.2 Is Still Looking To Be Power Hungry