That is, to punish, or at least jerk back, those magic-wielding characters who point out the fictionality most forcefully, those characters who play the part of the fantasizing writer and reader. Ray, in this case. At first, Ray retreats to his fictions but stays safely on the outside, using the minimum of authorial intervention. Then the fiction draws Ray in, making him a character in his own fiction, and turning the narrative voice into a narrator. Summarized like that, it sounds pretty dismal, but Shiner is actually refreshingly upbeat about it.
Ray approaches art as therapy, or self-expression.
Whereas it's actually a living and an industry. It's not like he doesn't push it as far as he can. It's not like he's a coward. He almost dies, for crissakes. He earns his right to stop.