That, by the way, is reason enough for me to call orchestra members and similar players musicians.
Ya never know. Many people that don't know formal theory or that don't read think of classical players as italic/capital letter
Musicians. But the same respect can be reserved for those that can improvise wonderfully and maybe can't read a note. This is a bit long-winded, but a composer told me a story that I found quite interesting...
This guy was older, and during the 1960s he was trying to break down barriers between the classical and jazz worlds. So he wrote a clarinet concerto that was scheduled to be debuted by an acclaimed clarinetist (who was left unnamed), and he left the cadenza blank. The clarinetist asked the composer what to play and the exchange went something like this:
Cl: You left the cadenza blank. When will this be finished?
Comp: It is. I just want you to improvise the cadenza.
Cl: *blank stare*
Comp: Just play what you want. The intent is for you to put some of your ideas into the performance.
Cl: I don't do that; I interpret what has been written.
Comp: Just try it; have fun with it, it'll be great!
*Clarinetist leaves and returns multiple times; each time he reiterates that he doesn't know what to play and demands that a cadenza be written. Each time the composer refuses. Finally rehearsals are beginning and the performance date is approaching, so the performer is growing increasingly desperate*
Cl: Look, my reputation is on the line here. You HAVE to give me something to work with here!
Comp: *sigh* Fine. Here are some of the tonalities you could move through: *writes out a series of arpeggios to suggest scales and chord changes*
During the debut performance, the composer watched in disbelief as the clarinetist proceeded to play the arpeggios exactly as written, playing each note for an equal length of time.
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My conclusion is that this guy may have been a great instrumentalist, but he was not necessarily a great musician. He may even have been an expressive interpreter of the works of others, but he was either unable or unwilling to express himself which is one of the aspects that we take for granted in good musicians.