Yeah, he did want to gather info on pein and akatsuki, but i think youll find once he realised how strong pein was (that he defeated the previous hidden rain villages kage, the guy who made him a sannin) he was fighting to his most.
ye but thing is jiraiya had no intention of fighting pein really he was just trying to gather information not trying to kill pein so we basicly still dont kno his true strength and i still think no matter what jiraiya can take itachi alone
He even stated in the manga clearly that his strongest fighting style, hermit mode, was no good.
Itachi has yatas mirror, which specifically states by zetsu is an legendary item that deflects all attacks, and the sword of totsuka which susano holds.
I dont get this whole "chakra over-use"
tell me one character that has died from "chakra overuse"
Once youre out youre out, you cant overuse chakra because chakra doesnt work on a loan system, if you have none-youre using none, simple as that.
Itachi can dodge rasengans easily, the fight with sasuke is a little contradictory, as his movements arent the best, but he is the fastest ninja known, no one beats him in reflex speed, his seal formations are faster than what kakashi can do, and to pull it all off the 3 sannins are useless at genjutsu.
Jiraiya himself stated hes not good with genjutsu
Tsunade is all about raw power so logically-she wont be good against it either
Orochimaru doesnt appear good or bad at it, neutral.
Not just that but nobody can get out of a tsukynomi, hed own them all easily.