Im not even gonna waste my time with gathering all the scans of hiruzen using other people's jutsu.
Hiruzen knows all the jutsu in the leaf excluding KKG's.
And what does "every jutsu in the leaf" stand for? The vast majority is probably just a bunch of elemental jutsus. That matters as much as Kakashi's 1000 copied material which only serves to hype a character's skill.
We'll never get to see Hiruzen performing a Ino-Shika-Cho combo because those skills are exclusive to certain families. Same goes for FTG which isn't the random jutsu any fodder Chunin pulls off.
When Oro mentioned that he most likely meant everything that anyone in Konoha can learn according to their level, jutsus developed by and for the random Konoha shinobi (even Hiruzen himself invented his own jutsu) that don't belong to remarkable and specialized families.
But only Hiruzen could learn everything and perform all those jutsus with the utmost efficiency. That's where his genius lies.
He has already replicated the Death Reaper Seal (after only seeing it once)
He duplicated Garururu's 5 elemental stream after seeing the hand seal
So yes hiruzen can copy jutsu without a sharingan.
He had time to learn about RDS after seeing it. Minato learned it somehow and it wasn't because someone performed it for him.
He already knew how to perform the five elements and he simply shot them in large quantities.
Lol for real? I repeat, not even Sharingan users copied exclusive stuff like FTG. Now Hiruzen's eyes > Sharingan?
Are you serious or are you trolling? >_> I never know with other Hiruzen fans.
And even if they nerf minato, they cant nerf FTG. Its a technique that hiruzen still had to deal with.
Well, Kishi kept Minato in his grave for a reason.
Tobirama also used FTG and he never showcased it against Hiruzen. In fact, he was renowed for his speed, not for his Suiton (like we were led to believe earlier).
Edo Minato would've probably attacked with his unkown chakra nature or Rasengan, but definitely not with FTG.
Anyway, i gave my input, but you didn't answer my last question: "Why do you claim readers have a hard time accepting him as the GoS?".