Don't know, if someone noticed that before...

but didn't sasuke use chidori 4 times in one day ??

ep 83 - 2 holes in the rock, sasuke's doing chidori for the third time, end of scene...

sasuke hears about itachi and naruto, finding 'em and doing chidori for the 4th time on itachi in one day... (and has his hand "burned" by chidori, but after all he managed to do it normally...)