You already told us, you stole from your own blog 😛

But as an honest guess, I think you were just exploring SQL Server, and eventually found the DMV for the rules. Of course one important piece of information is the DBCC command list, maybe you got that from http://www.novicksoftware.com/tipsandtricks/tip-sql-dbcc-help.htm or just from http://msdn.microsoft.com/en-us/library/ms176040.aspx.

In general I assume there is no single source of information, just lots of experience & knowledge built over the years, and a lot of exploration to build that knowledge over time.

Or do you just have some really good contacts with MS?

I am curious 🙂