Hence the reason, to quote Kirby the Great, "comics will break your heart".
This debate does pose interesting questions. Is the dialogue more important than the written scenario? Which counts for more? 'With great power...' or the situation of Peter letting the burglar go who ended up killing his uncle. "With great power..." existed as a quotation for more than a century before AF#15 and it never had the resonance it did or popular favor until Spider-Man, and I'd argue that it was the situation of the plot that gave that the meaning it has come to acquire. And it makes far more sense to assume that Ditko came up with that then Stan Lee did, it shows that writing good dialogue doesn't exist in a vaccum, not without strong material to react against.
If you read the stuff that Stan Lee wrote, he hardly ever mentions specifics. He would always say "I intended Peter to be troubled and so on" but he would never break it down in terms of characterisation of Peter or plot. There's no interview or article where Lee talks about how he came up with the twist of the Burglar being the killer of Peter's uncle and that's rather surprising. Gerry Conway in interviews for instance will walk you through specific scenes of The Night Gwen Stacy Died and specific moments in the stories where he talks about intentions and meaning behind some scenes, like the Epilogue of ASM#122. You see that with other comics writers. But with Lee you never get any of that. Whereas Ditko's published letters go much more into that, Ditko wanted more realism in Spider-Man and often reacted against Lee's outlandish ideas, but on occassion agreed with Stan when the latter's ideas made sense (such as Lee vetoing the idea to kill Betty in a common accident) and aligned with his sensibility for the story's tone and Ditko wanted Spider-Man to be somewhat realistic and individual and didn't care for Lee's ideas like the issue with the aliens at the start with Tinkerer. Ditko said that experience made him convinced that he should just ignore Lee's ideas for plotting. The Green Goblin was supposed to be some mummy in the desert that Ditko converted into a guy on a glider.
Compare Jack Kirby and Stan Lee's observations on Doctor Doom:
"I had a hand in creating Doctor Doom...Doom is a very tragic figure... I like Doom. Doom has got a lot of class, he's got a lot of cool. But Doom has one fallacy: he thinks he's ugly. He's afraid to take that mask off. Doom is an extremist; he's a paranoid. He thinks in extremes... if Doom had an enemy, he'd have to wipe him out. And if Doom thought that anybody was smarter than himself, he'd kill 'em, because Doom would have to be the smartest man in the world."
— Jack Kirby, Kirby & Lee: Stuf’ Said!: The complex genesis of the Marvel Universe, in its creators’ own words, by John Morrow.
"Everybody has Doctor Doom misunderstood. Everybody thinks he’s a criminal, but all he wants is to rule the world. Now, if you really think about it objectively, you could walk up to a policeman, and you could say, 'Excuse me, officer, I want to tell you something: I want to rule the world.' He can’t arrest you; it’s not a crime to want to rule the world."
— Stan Lee
Between the two of them which guy sounds like he has a grasp on the character of Doom and knows what they're talking about? And this is from somewhat contemporaneous interviews in the '60s to early '70s.
What we have is the original art. That's all you have. There are no other documents aside from the art. As the joke goes, while we have no evidence that Lee actually orginated or created any of these stories, we have definite evidence that the artists drew the stuff and actually did write in suggestions for scenes, plots and characters.We desperately need a copy of the notes Ditko and Kirby left to Stan to know what the latter did/didn't contribute. Are there any surviving copies of those that are public? Did Riesman find any himself?
In the original art you have the pencils and sometimes you have comments by Ditko or Kirby to Lee about suggestions for what the dialogue and the scene should contain. Now the problem is that Marvel only ever returned a small sample of the original art to Kirby and Ditko and his heirs. Kirby drew more than 20,000 pages but he got back something like 1,900 pages. So you can't do step-by-step documentation issue-by-issue. In the case of Ditko, dude has clammed up and holed up. There are rumors and legends that he used his original art as a cutting board but that's been debunked by his nephew so if he had his original art he kept it to himself. There's also been rumors indicating that Stan Lee himself has hoarded garages full of Kirby and Ditko's original art in unopened boxes but so far this hasn't turned up yet (and considering the mess that Lee's estate has fallen into, it'll be a while before we solve the story).
There's a wonderful tumblr site called "Kirby without Words" (https://kirbywithoutwords.tumblr.com/) that compares some of Kirby's original art with his suggestions to the finished issue to try and gauge what Kirby did and what Stan Lee did. And some of the results are interesting. It's generally observed that Kirby's original drawings often showed or indicated female characters far more capably than the dialogue actually indicates. In some cases, Stan Lee's dialogue essentially undercuts women. Like this one here (https://kirbywithoutwords.tumblr.com...e-are-some-who) where Kirby's original dialogue suggestion has Sue saying "You Barbarians" and Reed saying: "Easy, Sue" and below a panel that shows Susan Storm enraged and Reed holding her back. In the actual finished issue it's converted to Sue going, "Stop him Reed!, They can't defeat us again!" and Reed saying "They won't Sue! I swear it!"
That's why people saying that Kirby's dialogue was worse than Stan Lee's is essentially meaningless. Bad in comparison to what? In this instance, Kirby's dialogue was shorter (just four words divided to two characters) and indicated character much more boldly than what Stan did.