Wondering how you figure that Dunrovin does not have English Shepherd in it since some of those dogs are part of the registered English Shepherd breed pool... 

I love looking at history and tracing out where various dogs/lines came from, but the more I do it the less linear breed history becomes ;-)... it's a web.  Lots of overlaps and intersections between currently recognized breeds.  That doesn't make breed identification meaningless, I think it simply means that folks interested in maintaining distinct types need to focus on attributes of their current dogs and worry less about whether or where remote ancestors were registered.  

Mary