I've wanted to learn more about this to understand the processes involved - not that I could use wet equalisation since I dive in cold fresh water
. (The mouth version would work though I guess- I understand that method.)
Is it not critical to keep the soft palate shut to prevent water from passing down into the upper throat, especially when in a head up position? If the nasal cavity and sinuses are full (or nearly full) of water then it must surely be very important to keep the soft palate closed - presumably for the entire duration of the dive. Any relaxation of the soft palate would mean that water leaks down into the back of the mouth and throat. This sounds difficult to deal with and not something I would like to try in a hurry!
The method of allowing water to trickle into through the nose to reduce the dead air space sounds much less risky to me, but perhaps not as effective.
alun
