Precisely. I don't assume any documentation is accurate unless I've verified it matches the behavior of the code - and I've run into some doozies in my day.

The worst was a custom-built copy protection scheme that was built by a former (?) software cracker who designed it to be difficult for someone of his skills to reverse engineer. It took me a week tracing through the code to understand what it was actually doing so I could extend it to add more options.