I think if you'll carefully reread what I said, I didn't say that optimism was the problem. I'm 100% positive that I said that flippancy is the problem, a word that has a very specific definition. If you (general you) are being flippant, then you're likely to offend people in this sort of situation. That, after all, is what the word means. On the other hand, if you're not being flippant, then, obviously, you're not as likely to offend in that manner. It's pretty straightforward, really. If you (general you) are so world-weary that you're confusing aliens or Bermuda Triangle inversions with optimistic theories, then I can't help you. Seek counseling and/or go on vacation would be my best advice.