The splitfire is snake oil. Multiple electrodes have been hyped for years. They are just stuff to sell.
No matter how many electrodes are on a spark plug, electricity takes the path of least resistance. This mean that the spark will jump ONLY on one of the electrodes at a time. In some cases the spark will be fatter. In the days of point ignitions, spark plugs could sometimes make a big change because there was very little energy. Modern engines, however, have FLAME THROWER ignition systems, making for rare cases where spark plugs can be a performance advantage.
Due to the expense of platinum, the electrodes are indeed thinner making a thinner spark. This can under very specific circumstances indeed cause a SLIGHT performance loss. Unless you enjoy changing plugs every few thousand miles, however, the factory platinums will, over the long run, provide better performance.