A nice little article about defensive programming
Shahar Prish, one of my fellow teammates on the Excel Server (now called Excel Services by marketing) team has written a nice little article on defensive programming that I thought was pretty insightful. And no, I'm not Dev1, Dev2, or Dev3. :)
https://blogs.msdn.com/cumgranosalis/archive/2005/12/12/DefensiveProgramming1.aspx