In a project without version control (or one that doesn't trust it enough) there are always whole sub-programs made up of dead code. It's usually some combination of commented-out blocks and functions that are only called from within those commented-out blocks. Removing commented code (not real, descriptive comments) is the first step to eliminating all this dead code, and eliminating dead code buys a ton more flexibility in what you can change safely.
Fully agreed, I was tasked with using an old library and my first order of business was to make an analysis of dead code branches. The GIT commit removed 17 out of 80 files and about 10-11% of the code in some other files (that were not deleted) and the library works 100% the same -- confirmed by tests that I painstakingly added during the last weeks.
