Why lip buzz or mpc buzz or leadpipe buzz. What is the difference. Besides I heard that a study showed we don’t have to buzz.
Many great teachers advocated lip and or mouthpiece buzzing (to certain students).
They are used as exercises and to teach a certain concept. After the idea is understood the buzzing is stopped.
Leadpipe buzzing has more to do with AIR-flow while lip buzzing deals with Strength, range and a close embouchure setting. Mouthpiece buzzing is normally to work on a dynamic embouchure rather than static one. So that your embouchure can always adjust and shift registers as you play.
Strength exercises are short lived so as NOT to impede lip flexibility. AIR exercises are forever.
FWIW we’ve known since the early 60’s that there is a standing wave setup in the tubing of the trumpet. I first read Schilke’s report in 73 or 74. The fact that a buzz is not required does not mean that the skill learned doing it is not important.
If you only know how to dogpaddle then you can “say” you know how to swim. I doubt that a dogpaddle would win a swim meet however. Knowledge and skills always pay off.