BigGreenMat said:
If you go back though Kakashi is pissed at Gai that he taught Lee to open his gates.
He was upset that Gai taught Lee the Ura Renge, which involves enough Gates to endanger the user's life.
Omote Renge
is forbidden, but Kakashi didn't make a fuss about it.
but Naruto copied Sasuke's air combo too.
He produced a similar combo through his Kage Bunshin, but he didn't "copy" it as Sasuke did.
<Gai> Mastering even part of the super Taijutsu "Lotus", is impossible without grueling training... Even with the Sharingan it's not something that can be perfected that quickly...
Part of the reason Gai considers it "impossible" is due to the Initial Gate required for the entire combination.
Also when he fights Rock Lee before the Chuunin exams he uses Sharingan while fighting Rock Lee and notices that it is useless because even if he sees the attacks it is no use because he is too slow to do anything about it. So Sharingan is really no help against Taijutsu.
Sharingan is a huge help against any technique, Taijutsu included, as long as the user's body is able enough. Whether it's speed of an enemy's Ninjutsu, or the body speed of their Taijutsu, the Sharingan can allow the user to see through it, but their body has to be up to snuff in order to copy and/or defeat them.
Taijutus has never been a special case against the Sharingan. Sasuke was outclassed because his
body couldn't keep up.