So what you are saying is they have changed the procedures. It would be interesting to see a source for that and when the change took place.
1. Here is information from a submarine history site. It is a direct quotation from Our Navy magazine.
Here is an excerpt:
“Buoyant ascent—or ‘blow-and-go’ as submariners refer to it—was approved as the primary means of escape two years ago by the Chief of Naval Operations. Since then, more than 7,000 men have qualified by buoyant ascent at the New London training tank.
“This escape method works like this: An escapee, wearing a ‘Mae West’ life-jacket, exhales almost completely and then begins his ascent, exhaling the entire trip to the surface.
2. Here is a site from the United State Naval Undersea Museum showing the history of submarine escapes. It mentions the same "blow and go" technique, but it does not have any information about that being abandoned.“This escape method works like this: An escapee, wearing a ‘Mae West’ life-jacket, exhales almost completely and then begins his ascent, exhaling the entire trip to the surface.
3. Here is a 2021 study. It does not give a detailed description of the ascent technique. Here is the only thing it says about it.
students are given individualized refresher instruction on ascent technique. This includes practice saying, “HOOYAH,” in a manner that maintains a patent airway while diminishing undue glottic pressure as the trainee surfaces. Exhaling to the surface relieves lung expansion and instructors place great emphasis on never breath holding during ascent.
4. Here is a modern Navy video. It clearly shows the ascending diver shouting "Hooyah" to expel air from the start of the ascent.
So that's all I can find for now. I await the information you can provide that shows that all of this is wrong.
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