>>he knows a lot more about them than most people.<<
But as Monica said, I don't know everything.
Getting back to the Britannic and the Lusitania, it helps to know that both vessels sank in reletively shallow water. When they rolled over, neither was able to go down far enough to right themselves before hitting the bottom.
I seem to have missed Phillip Ivey's post from last year. I think he may have been thinking about the Lusitania in connection with an asserted coal dust explosion. To my knowladge, no such connection has ever been made for the Britannic and the evidence from the wreck doesn't support it in any event. The break in the bow comes from the enormous bending loads imposed on the structure when it hit bottom before the ship was even completely submerged. Had the watertight doors down below and the portlights on
E-Deck been closed as required for wartime cruising in waters known to be mined and infested with hostile submarines (They weren't)I'm of the opinion that the Britannic would have survived.
The Lusitania is a whole 'nother smoke. While the coal dust explosion theory has never been absolutely ruled out, it's never been confirmed, nor it it really likely. The North Atlantic is fairly cold even in the summer time and Lusitania was crossing in early May. What this would have meant was that in all likelihood, the bunkers would have been dripping with condensate and turned any coal dust into a nice tarry goo, not the fine cloud of dust needed for an explosion.