Frindley, I don't think your proposal will work: John's algorithm converts ASCII codes to their lower case equivalents. The Cyrillic characters I used aren't part of ASCII, so they bypass the conversion.
Bilby and reesetee: there's not much overlap between Cyrillic and Latin, so the end of the world is not approaching: schadenfreudgeon and most other words can't be entered in all caps. Also, searching for banana will not find ΒΑ�?Α�?Α because of the mismatch between ASCII and Cyrillic, so any word entered that way would rarely be seen once it scrolled off the home page (e.g., 音�?).