In one chapter he discusses the confidence and edge that is developed by night after night of performing on the road and the difference between a great night and a good night. This was the most interesting, and most relevant part for me. He says basically that "It's easy to be great". The nights where everything clicks do come along and can be counted on to some degree. The real challenge is being consistently good.
I have read other accounts of this same thought; Lieb speaks about it in Self Portrait of a Jazz Artist and many other heros have voiced similar thoughts. I find it encouraging to see that very successful creative people sometimes struggle with the same things that we do.
The idea of "just doing it" everyday and developing a long view of your work is difficult to develop but I think it is very healthy. I do post-mortems of my most recent performance or arrangement and for a time, that glimpse would color my mood (both creative and otherwise) for several days/weeks. To look at that work in the perspective of the "long view", I feel, gives me a perspective that is much more accurate. The real challenge in trying to develop is to be objectively critical and I think it is much easier to do that when you are working consistently without the "striving" for a great night.