In the World of Warcraft Battle Chest Guide, I found the following passage:

The issue here is that intentionally testing your class makes the process more analytic; you can prepare new strategies, test them out, and really see the effects. It’s MUCH harder to keep a keen eye out when you are surprised

To me, you could apply this to development without even having to swap a single word, due to the usage of words like class (though in WoW, this has a different meaning). This quote fits very well in any development of software I guess. It’s funny how a computer game can even remind you of such things 😉