Consider this a mere prelude to a longer reflection on the topic of conditioning, but like most of us horn jocks, I'm continually fascinated/horrified at the relationship brass players have to our mistakes. It's a staple of music school lexicon that the best way to eliminate mistakes is not to practice them, but is it truly possible for a brass player not to practice their mistakes? Ever? Seems to me that no matter how hard we try, unless we are both independently wealthy and exceptionally, pathologically driven, we are going to have days where the ol' choppers simply won't cooperate, whether by virtue of over- or under-cooking the previous day(s). A day off to rest may or may not be in order depending on the particular sonic malaise, and even if it is, it may or may not result in a real live "good day" when we return. Most likely, we need to play some, if not a lot, and it's not going to sound good, i.e. it's going to be one big "mistake," or a series of them. And if we simply sit around waiting for a good day, we eliminate the very possibility, in addition to earning ourselves days or weeks of restorative maintenance filled with "mistakes." If there is a solution to be found here, it remains a mystery to me.
My grandmother, who never played professionally but had an acute musical sense, once said that what made brass entrances most exciting was the suspense surrounding the heightened potential for something to go wrong. I'm now imagining some orchestra outreach type in a sport coat and tennis shoes proffering this alongside his allegorical interpretation of sonata form as part of the hidden code of classical music listening. He might be half right.