That was interesting, but I think their conclusion about the linux kernel being comparatively top-heavy with relatively few "work horses" was probably greatly i

That was interesting, but I think their conclusion about the linux kernel being comparatively top-heavy with relatively few "work horses" was probably greatly influenced by the fact that they only analyzed the linux kernel, not linux kernel + device drivers. IMO, device drivers should be considered part of the OS - really, the work horses of the OS, not called by any other code.