Ok, Sasuke has been incompacitated for a couple episodes, but we are only shown things in Naruto's perspective, not Sasukes, or any other character (besides the few cutscenes from the main story). That being said, you have to sort of guess that Sasuke has been learning new skills on the side, like before the whole Chunin Tournament. I mean, can you honestly believe that small scene of him in the desert or where ever with kakashi shooting that massive ball of power (can't remember what its called) is all he learned. Be realistic, he knew that before Kakashi, and Kakashi was just proving a point.
do you mean where kakashi was climbing the mountain to meet sasuke...
the place where gaara visits them..?

if so

sasuke only learned the chidori with kakashi...
all he did there was taijutsu training to get lees speed...
so he could use the chidori..