Original sentence: These novels are controversial among his readers, and some critics have written about them very negatively
Edited sentence: Heinlein's books of the 1980s sold well, in spite of some critics' lack of enthusiasm; many readers believe that those who criticize them are missing what they perceive as the books' irony and self-conscious parodying of both science fiction and literature in general.Many other readers regret what they see as poor efforts on the part of a great writer.Some feel that his later novels were not up to the quality of his earlier work, sometimes suggesting the quality drop stemmed from his illness in 1978, while others consider the period to include some of his best efforts.These novels are controversial among his readers, and some critics have written about them with impassioned intensity