A fanzine essay regarding the question “where do you get your ideas?” In this essay the author speaks of “Shambolain” (the death of his mother,) the then forthcoming Flesh in the Furnace” (Emphyrio by Jack Vance,) “Muse (his father,) and “Beastchild” (a friend returning from Vietnam.)

Specifically:
“The Flesh in the Furnace (Bantam–tentatively scheduled for January , 1972). Reading Emphyrio (perhaps one of the two or three most brilliant sf novels ever written and badly ignored), I came acress [sic] Vance’s idea of organic puppets, living miniatures who perform plays. He Tosses it away, using it only to make an important impression of the hero. I saw a book in it.”

This is most likely the passage in question. A footnote on page 14.

Energumen #10, Jerry Lapidus letter, p43:
“Most surprised at the Silverberg interview–that it was as good as it was. It’s just that these author interviews have a habit of being so patterned, so standard, so dull and uninteresting–and this one is a total opposite. Perhaps it’s Bob’s honesty and candidness that makes this exceptional, but whatever, it’s a really nice job. I particularly like his comment on getting ideas–“I’ve never had difficulty getting ideas–multitudes of them. They come when I read, when I stare out the window, when I listen to music, when I’m asleep; hey even come when I sit down consciously to dredge up a few.” This hits me just right, because Dean Koontz has an article in TA…7 saying that for him, it’s the exact opposite–the ideas don’t just come, and the article talks about where the basic ideas for some of his recent stories did come from. I hope
Dean reads this interview.”
[The Silverberg interview in question is in Energumen #9]

From DeanKoontz.com:
In the earliest couple of years of his career, Dean wrote a few letters and articles for science-fiction fanzines. He was not prolific in this area because he was too busy writing fiction to pay the bills and to learn his craft. Therefore, in 1991, Dean was shocked to learn that a person he had previously worked with professionally had, beginning in 1969 and continuing at least through the early 1970s, been writing letters in Dean’s name to individuals and had submitted letters, and even some articles, in Dean’s name to fanzines. The name “X” will do until the full story can be told in Dean’s memoirs. All of this information was first disclosed to Dean in 1991 when X provided a written admission of these activities, although he could not remember everyone to whom these forged letters and articles had been sent. Consequently, any fanzine appearances by Dean after 1968 are highly suspect unless they were submitted with a cover letter on his own letterhead of that time.