Say what you like about the seventies, but the publishers had their collective fingers on the pulse. "Criminally readable"? That cover is probably criminally indictable. Another absolutely brilliant find, Mark!
From the first, I set myself against "literature"; the story was the thing, and no amount of style could persuade me to select a story that lacked genuine, unadulterated horror. For those who wanted something high-brow there was plenty.