As Australian Defamation Law is to the truth of many matters being publically revealed...so officially imposed Book Limits would be to the continued improvement of the Standardbred Breed in the Southern Hemisphere. In a word, stifling.
The financial constraints imposed on studs/stallion owners by restricted books would at the very least greatly curtail and in all likelyhood bring to an abrupt halt the current shuttle sire business & we would run the grave risk of a return to the bad, bad, bad old days of genetic trash and race track never were's.
Not to worry though. As the great Muhammad Ali once said to Howard Cosell "It ain't gonna happen. All you can do is wonder and imagine". I can't speak for NZ...but here in Australia the mere mention of our Restriction Of Trade Laws would serve to knock down any such move in a heartbeat.