Hey now,
Sure you can fly it without a rudder, but not without a vertical stabilizer. But why? the weight of the control is ninimal; .32 oz for the servo, .1 for the rod and control horn. Less than a half oz. saved... And just what do you give up for this huge savings of weight? Ground handling, knife edge flight, crabing into the wind, hammerheads, spins, controled landing runs, slow speed control, flat turns, all of this goes away with no rudder.
If this is a weight thing, you're better off not putting a pilot in the model. If it's a cash thing, Blue Bird servos are only fifteen dollars, wire is twenty cents and the horn can be made from a bit of scrap plywood...
RobII