The logic of this old ruling is quoted:
However, the BBFC have now dropped this demand, meaning films can now be released in 2 cuts without having to worry about ratings. Now, the cynic in me expects this may have something to do with the upcoming Lord of the Rings: Return of the King EE release, which I'd place money on being a 15 rating. Just like the 12A certificate was introduced due to Columbia moaning about Spider-Man initially getting a 15 rating, I bet this dual release policy change is due to New Line/Entertainment in Video (the UK New Line distributors) moaning about LOTR: ROTK EE.Their reasoning behind not allowing dual ratings was two-fold, IIRC: The didn't want people to accidentally pick up the wrongly rated version to show to kids (I know this has happened in the States, for example, where 'Excalibur' exists in a child-friendly and a full-on cut), and they didn't want younger kids realising there was a higher rated version and being 'tempted' to try to see it.
Anyhow, from a Disney point of view, it means the long withdrawn Mulan DVD can now be released (with a higher certificate and no re-editing) and on a non Disney point of view expect a Goonies DVD release from Warner soon too (the 'fake' hanging in the prison break at the start bumped the film to a 12 while the previous video - which was released before the 12 rating was introduced - was a PG).