Yes I can read the code but the question above can not be answered by reading the code - much more helpful would be a comment what the _aim_ of some lines of code is.
And maybe the group working on and with that particular module has a list of decisions (not a mailinglist) and why they where made - so one could go back to the original decision (should be referenced in the code) and look up what the original intention was.
Do you agree that these information could help a lot in similar situaltions?
This is actually a feature built into CVS (and most other version control systems) called CVS Annotate that does exactly that: http://www.lullabot.com/articles/cvs_annotate_or_what_the_heck_were_they_thi... For every line of code, you can discover who made the change, when they made it, and why. Assuming the maintainer is following standard commit message patterns, you can also reference the original issue that has all the background information on discussions on the code that were had, the development evolution of the feature over time, and why the decision was ultimately made to commit it. It's a pretty awesome resource because it's automatically updated with every commit, without the need for any manual intervention or extra overhead. -Angie