Alternative Vote

I was actually doing a bit of devilling about my beloved Harriet Harman when I came across this demonstration of precisely how the alternative vote system works http://en.wikipedia.org/wiki/Labour_Party_(UK)_deputy_leadership_election,_2007
I'm not sure what this proves other than that things are never as simple as people make them out to be. Is this a way of finding the favourite candidate or the least disliked? Beats me.