Mekabar said:That's right, but it seems quite ridiculous that a fighter, who is threatening a wizard, just scratches his head helplessly, while the spellslinger takes a step back and begins mumbling and gesticulating undisturbed.
Do keep in mind that D&D combat is, in many ways, an abstraction. Initiative, and the sequential nature of actions that comes from it (the fighter does his actions, then the wizard does his) is a necessary evil, a way to keep manageable what are nearly-simultaneous actions.