100% Irrelevant. Its stated the Voices have the Emperors full power, which is why he has to change host bodies due to dark side corruption of his immense power.
Also i forgot to mention the SW fights an Emperor Amped Sel Makor.
Its stated in the jedi knight story that the emperor is in a weakened state. Lets not forget the fact that he just switched bodies its also stated that they had to strike when he is re gathering his power.