Why Fish SV?
During a cast, as you lure pulls line off your reel, the brakes work to keep the spool spinning at a manageable speed to prevent backlashes. If there are any elements that change the speed the line is being peeled from the reel midcast- your line will overrun and you have yourself a tangled mess. With the SV spool adjusting for you on the fly, braking pressure is maximized at peak spool speeds, and lessens as the spool slows to maximize distance. This allows you to achieve the best of both worlds- distance and maximum control.