It's called Kitchener because the Pines was a 1st World War army training base.
If you go to the Clipstone village website I think there are some pictures of the old army base.
If you look on Google earth there are some historical military sites marked, like trenches and machine gun stuff.
I'm not sure naming the trail after an old upper class warmonger was a particularly good idea, considering the millions of nameless blokes who died, but hey ho, what do I know?