I hear you, Bebop.... As a classical trombonist, you are not only expected to be fluent in four different C clefs (bass, tenor, alto AND treble) but as a jazz trombonist, expected to read very high parts in bass cleff, with stuff so high sometimes you NEVER get off the ledger lines!

Now add in the fact that as an English brass band player, the trombones (except for bass T-bone) play in Bb pitch, treble clef transposed (like a tenor sax player) it makes for some VERY difficult times. And forget any kind of transpose button.

I still, to this day, tend to think in Bb pitch, despite years in C (your first few years are the formative ones) and have to mentally transpose when I play the bone for a solo, and then go back to the keyboards. Every now and again, it makes for an interesting moment or two!

But sometimes, the ability to put yourself into another key can help you play some pretty fierce outside stuff simply by shifting your mental key center, despite the song not changing. Give it a try, you'd be amazed at how 'outside' you can get, and still stay relevant to the song!