Many years ago, I heard a radio report about a piece of software that could check for plagiarism by searching for similar passages. The developer of the software said that the most eager uptake came from the second-string universities - good unis, but not Ivy League or Bloomsbury. When asked why he thought the good unis weren't interested, he replied that he didn't know, but inferred that it was because they didn't want to admit to a plagiarism problem.