The price of a messy codebase: No LaTeX for the iPad - Valletta Ventures.
The first step in compiling WEB code is to run TANGLE to produce unhelpful Pascal source files. Thoughtfully the TeX build system includes a translator to produce compilable C files. Although WEB was hugely influential as the progenitor of modern source code documentation it is now obsolete, and modern extensions to TeX have been written in C. This is compiled alongside the translated WEB code. It is not hard to imagine the effect this has on the readability of the codebase.
Why programming is not yet as advanced as nature in evolution.