Slate Magazine has a post up on fashion historian, Hilary Davidson. She had noticed the quality of the costumes in Bill and Ted’s Excellent Adventure to capture the accuracy of the historical period they were representing. As a result she developed the Bill & Ted test to judge the costumes from period pieces. When asked what inspired the Bill & Ted test, she said:
It’s a story in two parts. I spent six years writing a book on Regency fashion, called Dress in the Age of Jane Austen. I have spent a lot of time looking at genuine Regency dress. But I also spent a lot of time in the last year or so doing a lot of tedious production work for the book. I watched a lot of films on the way. I love Bill & Ted’s Excellent Adventure. I was watching it in the background as I was copy editing my index or some tedious, tedious thing and just enjoying it. Then, we got to the bit where they kidnap Beethoven.
My eye is so attuned to Regency dress, and anyone who follows my Twitter will know that I get quite opinionated about Regency costume on-screen. I was looking at the background extras, and I suddenly paused it and went, “Hang on a second.” I rewound it a bit and went through it in slow motion and went, “You know what? This is really, really good.” It’s a 1980s teen comedy. You don’t expect a high standard of costuming. After that, I thought, well, that’s it. That’s my benchmark. If the main characters’ costumes in a Regency production aren’t better done than the background extras’ in a 1980s teen comedy, I think you’ve failed in the costume design.