As far as I know, /wait only increments in whole seconds, not half seconds. At any rate, I can manually go through a 3-step mudra much faster than a macro can. Most of your mudra problems will not be the speed of them (though it is annoying) but rather how the server thinks you didn't press the button or when you go to activate it, it'll play the animation, stop the animation, not actually do the attack, and then you have to do the attack again (if you haven't already hit something else because it looked like Raiton actually went off and thus ruined your mudra).