Since Acrobat 4, there as been no real concept of "base fonts" for Acrobat and PDF.
All fonts should be embedded, no "ifs", "ands", or "buts" about it.
If you have a PDF file referencing "Times Italic" but not embedded, Acrobat 6 and Adobe
Reader 6 will attempt to find "Times Italic" on your system. If not installed, it attempts
to find "Times New Roman Italic" and substitute that. Failing that, it attempts to use
its built-in Adobe Serif font. Of course, if your PDF file was created with a font named
"Times Italic" but with some oddball encoding or modification from the original Times
Italic font used by Adobe, by not having the font embedded you could end up with
rather strange results.
