So Jay Arr,
Let us suppose that we take your view that the ATSB reasoning is excellent and beyond criticism because you have been in the ATSB conference room! (very impressive). Why, with then did the Seabed Constructor with its state of the art AUV's find nothing? Self evidently because the search was in the wrong place. Why? because some of the ATSB assumptions were/are incorrect, and the one that stands out to me as being crucial is the one that assumed that the aircraft descended vertically/uncontrollably from its last estimated cruise position. If the PF of MH370 had in fact deliberately flown the aircraft west and over the Malaysian border to create a scenario such as this, then why would he have allowed himself to become incapacitated prior to observing his chosen outcome?
Throughout this whole tragic set of searches, the ATSB (as well as the Malaysian counterpart) have been reluctant to let data into the public domain, where some of the world's extremely knowledgable and capable scientists, engineers and aviators with a combined expertise far exceeding that which the ATSB has, might have made effective contributions to the analyses, and at a much earlier stage.
Seabreeze