This is NOT true.
I'm commenting here because there is a large body of people co-signing this type of comment.
***First of all, every one make sure that you dont confuse 2 different fights. Some people comment about the Rasengan/Chidori clash on the rooftop, and some people are commenting on the fight at the Valley of the End. I'm talking about the rooftop fyi.***
When naruto and sasuke clashed on the rooftop, Naruto never pulled back. His rasengan was stronger because he made it at a force that would KILL someone, same as Sasuke did. He realized from the beginning that this was no test of power but Sasuke charged enough force in his Chidori that Naruto knew it was FOR REAL--Sasuke could have seriously hurt/killed Naruto if he wouldnt have made a strong Rasengan. Which means he didnt hold back at all b/c the force of Chidori would have killed him if he wouldnt have gone all out. Kakashi stopped the clash before it happened so no one would kill eachother.
If we are talking about the Rasengan/Chidori clash at the Valley of the End, Naruto hit him in the Head possibly, where his headband is lol. I dont think he AIMED for the headband b/c at this point they are literally fighting to the death, or atleast Sasuke is, and Naruto realized this. The two techniques Clashed and it happened to scratch his headband, but this is more symbolical on Kishi's part. Most Missing Nin scratch their headbands on purpose to show they are no longer have ties with the village. FYI
-gHost Senju