Many industrial applications (CAD software, statistical analysis tools like older versions of SPSS, and scientific lab equipment interfaces) explicitly call Symbol Mt Normal.ttf by name. The software does not look for "a Greek mu"; it looks for "character slot 109 in Symbol MT." If the font is missing, the software crashes or displays blank boxes.
If you want, I can:
The term "deep post" could imply a few different things depending on the context: Symbol Mt Normal.ttf
Because it has been included with Windows, Office, and many other Microsoft products for decades, you can usually open a document using this font on another Windows PC without missing glyphs. Many industrial applications (CAD software