John Gierach is a trout bum, dedicated to fly-fishing with cane rods with everything else in his life coming some way behind in priority. He is also a magical writer, perceptive, illustrative, who communicates the joy of fishing better than any other author I have encountered. He will go off on a tangent about the importance of good coffee for pages, and just drop in the name of a fly offhand. He paints wonderful pictures of the Colorado countryside without getting lyrical. I am not sure if fishing myself, or reading about him fishing, is more enjoyable. Probably reading about him.
Don't expect technical detail, he is far better than that. Though he teaches you plenty about the how's, it is the why's that are important, and nobody writes better than Gierach about the philosophy of fishing, without seeming to.