Reading all the reviews for the new tennis games that use the WM+ got me thinking: why can't they make a decent tennis game? Apparently TW10 is great and actually feels accurate, so it shouldn't be that hard, right? The problem is yaw. Yaw is the rotation of something parallel to the horizontal plane. You can think of yaw as the way a bottle is pointing when it's on it's side on a table for "spin the bottle". The trouble with the Wii remote is that it has NO way of detecting yaw positioning. There's no internal compass that says which way it's pointing, just if it's tilted either to the side or up/down. Essentially the Wii remote is always only operating in two dimensions: Y (tilt) and Z (rotation), but not X (yaw). Now, think about how what happens to the Wii remote when you swing it like a racket, parallel to the ground: If you're looking at a top down view of the player it's first this position: _ then this: / Then this: | All yaw determined. So I figure the way the developers are translating Wii movement to the game is by way of the part of Newton's law that states that an object at rest tends to stay at rest. When you move the remote it senses a movement, but because it's missing a way of detecting yaw it's got to guess at the yaw orientation based on other factors including momentum and G-forces. This is problematic to say the least. Golf works well because when you swing the Wii remote like a golf club you're altering other dimensions, especially on the Tilt axis. Back when the Wii first came out I saw a youtube video talking about ways to get around the yaw limitation of a Wii remote. Most of the time it's negligible because there is the IR sensor that can sort of take the place of yaw, but only if you're pointing it at the TV... not really helpful for a tennis game. Any thoughts? Think I'm right? Any reason to suspect that my hypothesis is incorrect?