Now, even though I am a mere novice compared to you experts I will try to answer Rowuk’s question about why pedals are controversial.
I am only attempting an answer because I am consuming as much information as I can to learn about playing the trumpet, and there is indeed contractor information that can be frustrating to the beginning. On top of that, specific details are often elusive because so much is hidden behind the mouthpiece.
Here is what I understand from Eric Bolvin’s video on pedals. Pedals can be useful to address specific problems. So, it is important to learn how to perform them correctly “if” you are going to gain any benefit from using them. Otherwise, he says he does not use them regularly. I guess this is because he does not have problem with his playing that require the use of pedals.
The teacher with whom we both had a master class never mentioned them once; and he is a true great. He obviously never needed them. I guess it is like anything else in the trumpet world. If you connect with it and it helps provide the mental connection of what you physically need to do to play better, then it has value. If not, there is another exercise that will.
I wonder if “lip bends” are in the same category as pedals.