Shikamaru with her 3 in genjutsu countered that junk.
It's clear that Itachi could break kabuto's sound gen. Based on the progression of the fight, it was obvious that he was simply trying to look out for Sasuke like he always was.
Sasuke has susano'o yet itachi uses his to protect sasuke; So, what, itachi can't counter muki tensei with susano'o, now?
Sasuke has a susano'o yet itachi catches Kabuto's Orochimaru modification so it doesn't reach sasuke. What, Susano'o can't tank Orochimaru now?
Sasuke has a sharingan, but, yet again, Itachi doesn't care about himself and is more concerned with making sure sasuke stays safe; hence why he told sasuke to look into his eyes. He didn't ask sasuke to look into his arm to assist in breaking the genjutsu, sasuke decided to use genjutsu also of his own accord.
The manga is simple to understand if you're not trying to look for excuses... Tayayu's sound genjutsu is fodder; It's nothing on the levels of frog song which bound a rinnegan user.
I hear some rumors that Tayuya genjutsu can solo NV and a genjutsu expert like Itachi has no counter against it(he easily in couple secs known how to break it by the way...) so why Oro didnt used Tayuya to his adventige and easily take down Itachi with hers sound genjusu as many people saying this would happen.... Maybie cuz Genjutsu against Genjutsu expert would be stupid to use dont you think so NB experts? If it would work that would be the only chance Oro had and he had Tayuyas DNA he simply could absorb it like Kabuto did and use it himself....
Itachi can only counter visual genjutsus with his sharingan, sound genjutsu is the weakness of doujutsus users. Itachi couldn't use Susanoo and was paralyzed, Shikamaru only broke out by inflicting pain on himself which Itachi can't do unless he use Amaterasu on himself which would just injure himself. By the time he breaks free and put out Amaterasu, he'll already suffer some damage. You fail to realize that Sound genjutsu and visual genjutsu are 2 different things, Itachi has nothing to see thru or counter since it effects his hearing and not his sight.
Manga fact that Itachi can reverse visual genjutsus, and that's with his Sharingan which doesn't work on a genjutsu that effects the hearing and not sight.
What makes you think Oro had Edo Tensei up? When he used it on Hiruzen he was still new to it and didn't even know he couldn't summon Minato and Edo tensei wasn't even shown yet so nothing supports that he had it at that time (had it ready for use). Also it wouldn't be Tayuya alone, Orochimaru and maybe the rest of sound 5 would be there. They'll break each other out of genjutsus since Itachi only put 1 person under at a time. Tsukuyomi would just weaken him. This is part 1 Itachi after all.
It's weakness are somehow not hearing it, inflicting pain on yourself or not letting them prepare to use it (frog song and Kabuto needed a few seconds-a minute prep time). Itachi couldn't do anything of that unless he used Amaterasu on himself which would hurt him more in the long run o the fight and if the Genjutsu is used again then that's even worst.
Again, you're mistaking a Visual genjutsu expert vs Sound genjutsu which is not Itachi's expertist. He uses his sharingan with his genjutsu which doesn't do anything to sound base jutsus. Itachi's only way out is what he did with Sasuke or to inflict pain on himself which he couldn't unless he use Amaterasu.
Shikamaru used his shadowed to inflict pain on himself, what can Itachi do when he's paralyzed and can't used Susanoo? Using Amaterasu on himself is his only way and that would only harm himself and cost him in the fight as that continue.
Shikamaru with her 3 in genjutsu countered that junk.
It's clear that Itachi could break kabuto's sound gen. Based on the progression of the fight, it was obvious that he was simply trying to look out for Sasuke like he always was.
Sasuke has susano'o yet itachi uses his to protect sasuke; So, what, itachi can't counter muki tensei with susano'o, now?
Sasuke has a susano'o yet itachi catches Kabuto's Orochimaru modification so it doesn't reach sasuke. What, Susano'o can't tank Orochimaru now?
Sasuke has a sharingan, but, yet again, Itachi doesn't care about himself and is more concerned with making sure sasuke stays safe; hence why he told sasuke to look into his eyes. He didn't ask sasuke to look into his arm to assist in breaking the genjutsu, sasuke decided to use genjutsu also of his own accord.
The manga is simple to understand if you're not trying to look for excuses... Tayayu's sound genjutsu is fodder; It's nothing on the levels of frog song which bound a rinnegan user.
Itachi was paralyzed, his sharingan which is what he use to use, break and reflect is useless to Sound base genjutsus. His only way out would be to inflict pain on himself like Shikamaru and the only thing Itachi could do is use Amaterasu on himself which would do it's damage as he breaks out and put it out. It doesn't matter the level of the jutsu, it's how you use it, this was shown many times in the manga. How else do you think a genin Shikamaru could have hold like 9 jounin sound ninjas?
If Itachi could have broken out himself then he would have then disrupt Sasuke's chakra since as you said in the progression of the battles, Itachi took front seat yet here he didn't because he couldn't.