There is some interesting meta-gaming you can do because you know that there is exactly one solution. If you have a block that can be put in 2 situations excep

There is some interesting meta-gaming you can do because you know that there is exactly one solution. If you have a block that can be put in 2 situations except that in one case it may collide with the other block you know that the "collision" will happen otherwise there would be two valid solutions. This way you can gain information from a seemingly useless block.