Not sure about how accurate some of the breweries are. The one I know has been discredited and doesn't make sense anyway is London ale III being boddingtons. Though I used it in my boddies and it was a pretty good clone.
I can remember several years ago the author Graham Wheeler going through that list in some detail and came to the conclusion most are wrong. He did a lot of research of his own and worked with a lot of the brewery's named.