It is kind of far-fetched to talk about testing here.
Hmmmmm. Maybe I didn't make the smiley big enough. Let's try again:
guess it's just as well that Chapter 18 suggests testing everything before you deploy it! ;-)
The point I was trying to make is not
that you should rely on the testing to catch this problem, but that, if you don't catch the problem earlier, the testing phase should still do so.
In other words, (just exactly as you say) best practices ought to be an integrated process, so even if one practice introduces a problem, another practice should catch it. Which is precisely what my book advocates.