Bug 3390 Enabling ZIP compression in pdf generation to reduce file size
Enabling compression gives a ~26% *reduction* over non-compressed Type 3 font embedding.
ie. 4.5 K/pg (compressed graphic) vs. 17.5 K/pg (uncompressed Type 3 font) vs 111 K/pg
(uncompressed graphic).
It also appears that most other applications that export in pdf use compression by
default. (OO Writer, etc.) So this approach appears justified. One could always add code
to allow the user to select embedding mode and compression.