I'm not even sure why I'm bothering with posts such as this.....but oh well.
You have nothing to say that Kishi only did that because he was the current hokage. You have nothing to say that it was a mistake by Kishi. Kishi has had more than enough time to put out something contradicting Hiruzen's hype. He has never done such, and never will, because he has no reason to. Why? Because Hiruzen's hype doesn't need contradicting. It's completely fair. Even praised by a man who hated him, who also happens to be one of, if not the smartest ninja in the series in Orochimaru.
You have no reason to assume anything given Kishi has given us no reason to assume otherwise.
Kishi expects people to use common sense when it comes to statements he makes. Of course Hiruzen isn't going to know doujutsu techniques(which I stated, but you decided to ignore, I guess). Kakashi has copied over 1,000 unique techniqes in his what, 32, 33 years? However old he is? Why is it so hard to believe that a 69 year old man learned every non-doujutsu technique in Konoha? The man praised as God of Shinobi and Professor(again, statements that have never been argued against)...it's not hard to believe at all. He studied it, he wanted to learn it..and he did.
Kishi didn't expect to have such an immature, young fanbase, I don't guess. It just shows with your post, he expects people to use common sense, but they can't even do that. It's quite obvious that part 1 was a much more mature manga. Now we just have people shooting beams out their ass and people with special eyes who can create these giant guardians and all this bunch of crap. Might as well be reading Dragon Ball Z instead of Naruto.