It's possible that if you have packages that understand flags (config package, with flags in init(), for example) that if you include it after the testing package, or before. One of them won't accept flags. (because flag.Parse() has already been called)
You can't rely on the order of imports initialization anyway. See http://golang.org/ref/spec#Program_execution .. I believe that's also the reason, you shouldn't call `flag.Parse()` in `init()`
