Associate designer on the project, Mike Chrzanowski, points out that the game initially started with over 20 different gestures but was eventually simplified to include only five. With players constantly shooting webbing and tossing patriotic shields about, it was vital that the game could successfully recognize and distinguish between the various gestures. Tasking testers with repeating various swipes and stabs, the Vicarious Visions team carefully monitored the motions that resulted and how different players interpreted and reacted to the on-screen instructions. After countless coding and tweaking, they claim to have constructed an interface that is 97 percent reliable. While Marvel: Ultimate Alliance doesn't make the most extensive use of the Wii's controls, it does illustrate how game testing and control mechanics need to be adapted for the platform.
It remains to be seen whether or not other developers will go through as much trouble as Vicarious Visions did to differentiate between specific arm motions and mindless flailing (there will likely be several games that count on the latter). More interesting is the recurring issue of shoehorning game actions into motion-sensitive controls. There's a fine line between taking advantage of a platform's capabilities and tacking on new mechanics. After all, is it really better that you twist your wrist in order to open a door as opposed to merely pressing a button?