The problem with going through people's old email and such is the signal/noise is extremely low, and often of a timely nature, and may not represent the final outcome, especially if work has been done on a system after the fact.
What we need is testable documentation. I do IT work most of the time, and document using a mashup of Markdown and text snippets in a specific format for network documentation, all kept in version control.
I then have a motley collection of scripts and tools that run against my text files and do simple testing like pinging all the hosts mentioned, checking DNS entries, etc. Frequently I'll write up docs before I start work, then by the end of work, all the tests will past. It's TDD applied to network design.
What we need is testable documentation. I do IT work most of the time, and document using a mashup of Markdown and text snippets in a specific format for network documentation, all kept in version control.
I then have a motley collection of scripts and tools that run against my text files and do simple testing like pinging all the hosts mentioned, checking DNS entries, etc. Frequently I'll write up docs before I start work, then by the end of work, all the tests will past. It's TDD applied to network design.