*3.1.3 Flexibility of use and free-play*

An important aspect of simulation and gaming is the game-play flexibility. The function of flexibility is to make it easier for the player to take a playful attitude [29], in the sense that the gaming system will be able to conform to his choices and freedom of decision, and not force them. Game-play flexibility aim is to guarantee freedom of action, which must not be compromised by problems related to understanding the interfaces or by technical difficulties. Klabbers argues that the free-play dimension is part of the very specificity and morphology of simulation and gaming devices [8]. Free-play is the idea that users are free to play as they wish. The path of the simulation is never fully scripted in advance and it is impossible to say what the outcome of the simulation will be before it is played. In terms of game-play flexibility, haptic games have a clear advantage over computer interfaces because of their very nature as tangible objects which can be touched, grasped and manipulated in any desired way. They can be handled with a degree of spontaneity that Duke identifies as an essential element in his definition of gaming/simulation as a mode of communication capable of understanding the "gestalt"6 [7]. In haptic games, there is a degree of flexibility in using tokens and other tangible objects that is not found in computer interfaces [30]. The user can pick up the token, touch it, examine it in its entirety, whereas in the computer interface, there is always something hidden, symbolically speaking, that the user cannot touch. To put it another way, in a computer game handling is made through an interface built by someone else, whose logic and meaning may not readily accessible to the user, or may even impose itself to the user [2]. In addition, the physical pieces of a haptic game can be used more easily as a medium for communication between players. The players may designate a token or a space on the game board to inform other players of a particular situation or signal their intention. It is possible to provide this type of signalling and communication mechanism with a computer interface, as long as the interface is visible to all, for example by using a horizontal projection surface. Similarly, there is immediacy of action with a token, which is not always the case with computers, especially when several calculations are performed after a player's action. Lastly, the computer interface is developed according to the game mechanics devised by the game designers. If players want to perform an action that has not been coded in advance, they will have difficulty doing it by themselves because that action was not intended. They will first consult the game facilitator or, as the action cannot be performed immediately, will give up attempting that action. Physical game-playing components do not present any such obstacle for players. Players can pick up a game piece and use it for some other purpose or make it do something that was not intended. They can create new game mechanics spontaneously, such as hiding counterfeit money, substituting or adding game pieces, hindering the access of certain players to game resources by physical obstacles – these are all possible ways of hijacking game mechanics that are difficult to reproduce in computerised games.
