> The original character (𡚴) was not added to JIS or Unicode until much later and doesn't display on most sites for me
Why didn't they simly replace the original bad one?
> nine hundred pages. Imagine tracking down a single character without a page reference
Not that hard to imagine, OCR existed back then?
> Not that hard to imagine, OCR existed back then?
How do you train OCR on a character that doesn't exist though? Even these days, OCR often confuses the 52 Latin characters, so I wouldn't expect as good of results with older technology and some 20k CJK characters.
> Why didn't they simly replace the original bad one?
Starting with version 2.1 they made it so that code points can't ever be unassigned. People were getting really upset with the removals, since they can result in old data being misinterpreted. (Er, nothing actually was removed in 2.1, but it probably didn't become official policy until 3.0… ?)
Besides, it's useful to have the bad characters in there for people who want to write posts like this one discussing them.