Yes, and any good parent knows that you can't just fill your children's minds with rainbows and bunny rabbits, then expect them to become well adjusted adults. I think intentions are the key. If I express a negative observation about someone else, what are my intentions? If I am doing it solely for their benefit, then I have done a good thing. My conscience is clear whether or not he or she was willing to hear me. If I do it for that sweet, sweet sense of smug superiority, then any truth in what I say is irrelevant since the act of expression was entirely self serving in and of itself.