Here is Mark Gruenwald writing in a Mark's Remarks column in Iron Man #217 (Apr 87):

I don't let people use the word "continuity" around me. There is too great a difference between what most folks think it means and what it really means. In the strictest sense, continuity means a) the storyline of a comic strip or comic book, b) the transitional relationship between one panel's picture and the one that comes next, and c) the sense of cohesiveness and connection between one story, episode, or issue, and the ones that precede and follow it. So what do most people mean when they use the word "continuity"? They mean "a slavish single-minded devotion to trivial details found in ancient storylines and a strange compulsion to resurrect and glorify said details at the expense of other story values." That, my friends is indeed a problem that certain comics writers have been afflicted with, but that isn't "continuity". That's an obsessive love for trivia.

As I write this, Marvel Comics is celebrating its twenty-fifth anniversary. That means that certain titles like FANTASTIC FOUR, THOR, and IRON MAN have been continuously publishing the exploits of its title characters for a long stretch now, generating untold millions of bits of trivia in the course of the ongoing storylines. Many but not all of those millions of trivial bits have been self-consistent. What is to be done about those few bits that are not? Ignore them, explain them, or devote a three-part epic that explores in vast detail why the discrepancy was actually a major subliminal scheme concocted by a deadly criminal mastermind? If you answered the latter, you probably suffer from the popular misconception of what "continuity" is as defined above. As the co-writer of the MARVEL UNIVERSE HANDBOOK, I see minor discrepancies all the time. Some of them have to be dealt with in order to compose a coherent history article fora character. The most recent example that comes to mind occurred when reaching the Zodiac entry. One account claimed that Nick Fury's brother Jake was the original Scorpio. A later account claimed he was the second Scorpio. So which do we go with? The evidence was equal for both hypothesis. We had to choose one over the other. We did. While I suppose a story could be constructed about who the original Scorpio was, it is not exactly one of the pressing concerns of our readers today (not like the identity of the Hobgoblin is). So if a writer came to me with a story about it, the idea alone would not be enough to convince me to go for it - it would have to be a mighty good story for me to want to devote 22 pages to it.

I was once asked if it were possible to write a great story about a character that violates the character's "continuity". I assumed that what was meant was a great story that contradicts some bit of trivia about the character - for example, what the name of his high school English teacher was. The answer is of course that it is possible. But a conscientious writer (like all of them who work for me) will not go out of his or her way to do so - that's childish. What is most important is that a writer stay true to the spirit and basic legend of the character. As editor, it's my job to see that he or she stays true to the wealth of sometimes trivial background details.

Some strawmen in there. But it's interesting that a lot of what's written here i could easily attribute to Tom Brevoort in 2014 if i didn't know better. And i think it's funny to see Mark Gruenwald complain about a slavish devotion to trivial details. I can't think of any writer who more exemplifies that phrase. I actually think it's his best attribute as a writer! But at the same time, despite everything he says, that last sentence is i think the key difference between then and now. Sure, don't worry about the name of a character's high school english teacher. But the editor is supposed to make sure the writer gets most of the details right. For better or worse, the editorial philosophy today is that the story comes first, regardless of what background details it ignores.

The funny thing is that Gruenwald DID approve a three-part story explaining who the original story was.

That should be "the original Scorpio was".

Interesting, too, that he specifically mentions the Hobgoblin identity, which will later be retconned in an unholy mess of confusion. (It was that one background character we never saw! And, uh, he had a twin or something?)