Is Being a Wet Blanket a Good thing?

I can't help being a wet blanket. I would like to think that I've have trained myself not to be surprised by learning to look for problems and all the possibilities, while considering the odds they can occur. So I can't help but see problems a lot and often.

I don't live a pessimistic or cynical life just because I see problems often and in everything. I find it relieving to be able to see them before they show up when I can't do anything much about them. Part of being able to solve them is to be able identify their importance and relevance. Surprisingly that is actually a critical thinking skill, as it related to overcoming cognitive biases. It is a cognitive bias to get hung up over problems and be unable to solve them. How effective can one be getting emotional on a problem that can be solved rationally.

In RPGs being a very meticulous critic is part of being a GM. Seeing all the problems and choosing which one's to emphasize is part of the craft. Especially since players, ideally, act creatively (and thus unpredictably) to solve problems put before them. When they put a solution, I as a GM, use philosophy and critical thinking to silently note all the assumptions and introduce uncertainty into them.

The players and the Gm are the same in problem solving capability. The difference is that the GM knows which assumptions will give way to problems, and the Players have to figure it out by sorting out the GM's clues and effective question asking.

When the GM "knows" where the problems are, he shouldn't usually make it a 100% certainty. Ideally, the GM applies that same chance factor for all possible problems. So even He doesn't really Know certainly where the problems are, and just makes sure the Odds of the bad things happening follows through when the dice say so.

Check out Wikipedia's List of Cognitive Bias. Spotting those and Logical fallacies can be a source of fun in a game. Fun in the sense that everyone is trying to map out their thinking and problem solving habits, and cooperatively bolster the weaknesses.