Interesting. I have spoken with one experienced audiophile who knows both well...he did not care for the original Wilson crossover and used to recommend others...but feels the current crossover is excellent and far superior to the older one.
As far as I remember the Watch Controller was designed by Richard Marsh, of Marsh Sound Design. The old WatchDog included the Watch controller and a MSD 400W amplifier - I know of someone who bought an used Watch Dog at a nice price just for the electronics!
I am not sure of the differences between current and older Watch Controllers.