The International Association of Amateur Heralds

Brevity is desirable, but clarity is more so.

Also in this case, as well (or poorly) as I can make out the text of the certificate, the ermine spots are not at the end of the blazon, so if Sable is omitted the ermine spots would presumably match the next color mentioned - so clarity IMO is better served by specifying Sable for the ermine spots.

Mike McCartney wrote: “Brevity is desirable, but clarity is more so.”

Most definitely. There is sometimes a fine balance that needs to be struck.