I sympathize with Ricardo Padrón. From one perspective, canonical authors like Cervantes or Lorca seem critically exhausted, and the challenge of saying something new about them is daunting. Why add to an already substantial "critical industry" if you don't have something groundbreaking to say?
I would suggest, though, that what makes an author canonical is precisely the shared cultural fiction that his or her work is inexhaustible, that the conversation about certain works of literature can never reach an end. From this point of view Ricardo's question is framed backwards: it is precisely because of the interminable chain of discourse about the canon that the canon becomes the canon. This is Borges's idea. A classic is "aquel libro que una nación o un grupo de naciones han decidido leer como si en sus páginas todo fuera deliberado, fatal, profundo como el cosmos y capaz de interpretaciones sin término."
Out of fears similar to those of Ricardo, I held off on writing on Lorca for many years. The first line of my book about Lorca, Apocryphal Lorca, is "This is not a book about the Spanish poet and playwright Federico García Lorca." In other words, "Ceci n'est pas une pipe." I was nervous about having something new to say about Lorca so I wrote a book about Lorquian apocrypha in the United States. At this point, however, I am ready to start working on Lorca "himself."