I was quite impressed with the endoscopic sojourn into the live specimen, to see those branchial hearts beating in real time, wonderful stuff! With regards to the "Big Squid" truly being Architeuthis dux, it could well be, regardless of accepted wisdom regarding distribution. If the span of those arms is indeed 30 feet as suggested (I would say a "slight" exaggeration, but please, correct me Scott, if I'm overly skeptic) they would be substantially longer than on any recorded A. dux specimen. This imagery was surrounded by much speculation, being marred by some ridiculous image analysis on Monsterquest, but with 5 billion giant squid around, indeed, who knows...
One thing though; "this animal probably feeds on whales"... Enthusiasm? Then again, there are many wounds on large sea animals that look exactly like cookie cutter shark bites, including some on a pygmy right whale, I personally looked at, that are incurred at depths where cookie cutter sharks just don't live, but large squids just might. A squid beak will take out a fairly round bite, not dissimilar to a cookie cutter shark at first glance. The pygmy right whale, again, had one wound the size of a large lemon, If you take the 40-50 mm maximum LRL for Mesonychoteuthis, you'll see that a 70 to 80 mm bite is actually representative of a large squid indeed, if that's what's actually causing the damage.
Edit: I found this on the te papa blog
It was earlier blogged that the wounds on the whale were from cookie cutter sharks.
Te Papa’s Fish collection manager, Andrew Stewart, came to have a look and this is his expert opinion:
‘Based on where the whale came ashore, the scars are probably from the cookie cutter rather than the seal shark (a larger shark species found in colder waters).
Many marine mammals carry the scars from encounters with these sharks. They have been likened to a swarm of wasps as these sharks sometimes occur in schools.
Tuna fishermen hate them as the bites can significantly reduce the market value of their fish. Fortunately for whales, a thick layer of blubber affords some protection from these unique predators!’
To my understanding, Isistius sp. don't occur at the same depth as Caperea marginata, but what do we know?