As a retired captain for a major European carrier, and having flown A320 family as captain for 4+ years (just to establish some credibility).
Having previously favoured the decompression / start drills through descent first loop, that left me a little troubled in that if they had completed the memory drills to start the descent and therefore had donned the oxygen masks, I would not expect both of them to subsequently lose consciousness before completing the drills. The spinning of the altitude selector to below MSA I could live with, and the subsequent vertical and horizontal paths, and indeed the rates of descent, although as commented elsewhere, I would have expected a decleration to 250 kts at FL100.
What I would like to observe is that, whilst CNN/NYT are potentially being speculative, that the scenario they outline does at least fit the known facts of the flight path and lack of comms.
One thing that we can rely on is that background checks on the pilots will be have been high on the to-do list from the very start. Whether or not they show anything remains to be seen and just may be the reason the names of the 6 member crew have not been released. Time will tell.
Should this unpalatable theory come to be proven, then for sure there will be swiftly implemented changes. Let's hope they are better thought out than after 9/11.
Having said I had flown the A320 family, I finished my career on the B747-400 which had it's own dedicated toilet, which would be the gold standard.