Thick letter L or I displaying in Acrobat PDF files

It's common for applications that create PDFs to perform little tricks on reducing file sizes when creating a PDF. One of those tricks is converting straight rectangular shapes into open paths with a line stroke applied.

Text objects converted to raw outlines before or during the PDF creation process could see letters such as a capital "I" or lowercase "l" turned into these open path line strokes. The PDF will print properly, but on-screen display within Adobe Acrobat could look odd. Those line-stroked characters may look thicker than they should be.

The best remedy for this problem is preserving any text objects as live type and embedding the fonts in the PDF. The type objects will render on screen properly.