"Refrying PDFs - the good, the bad and the ugly (2008)" by Leonard Rosenthal

Refrying is the process of converting a PDF file into PostScript (or EPS) and back again to PDF.

Though this practice of at least a double conversion (PDF to PostScript then from PostScript back to PDF) is no longer as commonly used, our Support team still run into users who still refry PDFs for many reasons. For most part, refrying is a process that is frowned upon, though for some users, this process may produce good results. However, for other users, the same process might also produce bad or downright ugly results. 

One of the best articles written with regards to refrying can be found here: https://gwg.org/download/refryingpdf/

This article from 2008 was written by Leonard Rosenthal, a Senior Principal Scientist with Adobe Systems who currently serves as their PDF Architect.