Is that personal experience or a general research result?
Is the result better than with careful code reviews [of the critical pieces] (both after writing, but also short checks during development over a code listing and coffee)?
Intuitively, everything with coffee involved ought to be better! :-)
Better than some theoretically perfect practice of careful code reviews? I don't know. Better than code reviews as actually implemented everywhere I've worked? Yes. (In particular I find it's really hard to maintain the discipline of carefully going through each other's code when you know that most of the time you won't find anything)