Bit of insight into the Race Management technology here -   

I think that it was in the post race press conference about the on the water umpires had the necessary GPS enabled tools to decide on whether it was a penalty or not.  I would expect both Umpires (I think that there is an Umpire boat typically following each contender) to have communicated and both agreed prior to the "No Penalty" announcement being made.

Hi Barry, I think that I heard them say that the Judge's race management software has just such a thing and is why they were able to make a quick decision on Saturday.