I felt the darkness of TDT had more in kin with Stephen Donaldson's work, which I could not read. It had a bleak, dark, negative, destructive quality.
With the main character as the source of evil and destruction to others, I could not continue to read it. If Lewis wrote TDT, and had finished it, I wonder if I would have read the whole book.
Jo wonders who was homosexual in TDT. Nobody. It's this action the protagonist does of pumping his "horn" into people, it has a degree of sexual overtone that is not normally found in Lewis' writing. If it was written by Lewis, my guess is that he decided it was going in a direction that would not be helpful, no matter what sort of redemption was intended later in the story.
In ALL Lewis' other post-conversion work, he uses protagonists who can be called heroes, not anti-heroes. Maybe it is my distaste for anti-hero literature that has most fuelled my distrust in this manuscript.