I love this!
1. Physical set-up: I tend to lean towards the mess with a student's physical set-up as little as possible side of things but (and this is a big but!) sometimes it is necessary and solves many problems at once. Efficiency is the key to playing any instrument well and a proper physical set-up is essential to that.
2. Technique: You can't tell a great musical story without being able to do all of the technical stuff well (as well as in any combination.) Technique is not hard to teach or to learn. Or I should say it's not complicated to learn. The only hard part is having the discipline to do it. Having a technique like Denise primarily involves a lot of work over a prolonged period of time. How bad do want it?
3. Music making: That's the only reason I ever play the tuba. All of that work to get a good physical set-up and the decades of learning good technique only serve one purpose: to tell a great musical story.
4. Mental attitude: Attitude is one of those rare things in life that we can actually control. Again, playing the horn like Denise is a very long journey. Some moments, days, even weeks, it can quite hard to keep a positive attitude. Progress is not linear (it never is!) and that can be discouraging if we choose to focus on any one data point along that journey to draw conclusions about our worth as a musician. A great teacher gives a student tools to be able to keep a positive mental attitude, even when that student doesn't feel like it is justified.
And of course she is right about your weakest link. Leave any one of these four behind and you will be held back from realizing your true potential.
Thanks for the awesome quote, Denise!