One of the most significant validations of my disinclination towards taking composition lessons came when I overheard two graduate comp students sounding more like a couple of undergraduate performance majors. "When's you're next lesson?" one asked the other. "Tomorrow," he replied, in obvious anguish, "and I haven't written anything this week."
The successful imposition of a steady rate of production on the creative process is sometimes cited as an important exercise in compositional potency, akin to weight lifting in athletics, or long tones in brass playing. Assuming they can cut it, this prepares the student for a career as a Professional Composer, which entails accepting commissions with strict deadlines and turning out pieces to meet them the way bakers turn out loaves of bread every morning.
I once read, though I've forgotten where, that Webern's concept of condensation taken together with his relatively small output led some of his more devout followers to demonize high rates of compositional productivity in general. This, I think, would be just as much of a mistake as to expect everyone to be able to compose right on schedule.
It is becoming more apparent to me that I am not getting any better at meeting deadlines, and that my best work is done when it is undertaken just because, not only without a specific deadline, but also without any real idea of if or when it might be performed. I'm hardly the first person to feel this way, and yet the idea that Professional Composers must learn to deliver the goods on time in order to earn their stripes persists. Hence, though it's hard to say I'm happy not to have commissions piling up, I do see a silver lining in that I'm free to do what I want and write on my own schedule. I also am not any more inclined to see a composition teacher than I was before, since that would only earn me the worst of both worlds (all the deadlines, none of the performances).
See Satie's The Musician's Day for a piece of writing that captures the absurdity of scheduling time to be creative.