Playing with the Hope that Your Opponent Doesn't See What You're Doing
This was a lesson I learned during my chess days. Making moves while crossing your fingers hoping your opponent doesn't notice the slight flaw in your plan. Or jumping to another section of the board with the hope he doesn't follow where you've created a more emergent situation. The problem is that unless one is playing from behind like in a handicapped game where risks are a little more required this type of thinking is too dangerous. Most experienced players follow the rule, "If I can see it, my opponent can see it". So try to play out tactics where you can't see how your opponent can stop you, for if he does it means he really is the better player.