Actually there is 1 trumpet truth "No air No sound".
I like lip buzzing to help solve problems like:
A new player,I like it because there is no mouthpiece therefore no mouthpiece pressure. This means that the lip buzzing embouchure has to produce its own pitches, it is free to move and learns to move. It teachs a close setting ( this cures 70% of all problems ). It builds both endurance and strength.
a player with very poor endurance,
a player with a very poor range,
a player with a real embouchure problem,
and some others.
I use it for about a month in various amounts depending on the problem. Meaning only lip buzzing for a week and then buzzing some and playing some. However I have had lip buzzing only for extended periods like a couple of weeks. It depends on how fast the lips retrain (and how hard they work at it ). Then when the problem is gone the buzzing drops to a minute or so every day to check on the setting, air flow, ect.
I don't use mouthpiece buzzing at all. Players with too much pressure can still use pressure. Players with an open setting can close the lips using the mouthpiece. The lips are not as free to move. So many players with real problems use the mouthpiece for a crutch. So I take it away and make them learn to use the lips and air.
A collection of some past posts & information about my book.