Quesada explained in a CBR interview the ways in which JMS's version differed from what had been asked for.
When I was halfway through issue three of OMD, we received Joe's script for issue 4. After reading it, we (Axel, Tom and myself) all quickly realized that we had a problem -- the script we had just received was not the one we were expecting, and the events that were being set forth in that issue were going to conflict with the work that was already being done on "Brand New Day." I thought that perhaps Joe had forgotten some of the stuff discussed at the summit meetings and the subsequent e-mails and discussions that followed, but that didn't seem to be the case; this was the story he wanted to tell. In his story, Mephisto was going to change continuity from as far back as issues #96-98 from 1971. In Joe's story, Peter drops the dime on Harry, and that helps get him into rehab right away. Consequently, MJ stays with Harry, and Gwen never dies and never has her affair with Norman, etc., etc. And in the end, Peter and MJ are never married.
This, in my mind, while it neatly puts the pieces back in some way, was not what we wanted to do. First, it discounted every issue of "Amazing" since that story arc. Second, the series of events that it discounts in the Marvel U are too far-reaching to contemplate. And third, it had severe ramifications for the creators already well underway on "Brand New Day," the thrice-monthly "Amazing Spider-Man." In other words, there was just no way to tell Joe's story without blowing up the entire Marvel U and every Spider-Man's fan's collection. What we originally discussed with Joe and the group was much simpler and cleaner: The wedding? Something happened on the wedding day that prevented it from happening. The unsmasking? Mephisto makes people forget it; much like the Sentry, it happened -- it's just no longer remembered.
What Could Have Been: According to Quesada, JMS wrote the point where the new timeline diverged from the old one as be Harry getting into rehab back in the early 70s, thereby affecting relationships and meaning Gwen Stacy never died. Marvel's writers collectively nixed it beforehand because such changes would affect the entire Marvel universe and invalidate nearly forty years of canon, and with two issues done they had to scramble to change the remaining two at the last minute. (If true, this could explain why JMS wanted his name off those issues; but all things considered, take this with a grain of salt unless we hear JMS's side of the story.)
I'm sorry, but it would have been WAY more jarring.
In the current version, every story for the past 20 years pretty much happened the same way, except for substituting the marriage for a deeply committed relationship. That's it. Gwen's death? Civil War? The unmasking? Everything happened.
In the change that JMS proposed, which would have used magic as well (magical time-travel), Peter would have gotten Harry help for his drug problem. Norman wouldn't have lapsed back into being the Goblin. Gwen wouldn't have died. And Gwen would have STAYED Pete's girlfriend (try telling the MJ fans THAT-- And keep in mind the teeth-gnashing heard around the web when Pete woke up next to Gwen in HOUSE OF M-- an alternate reality that everyone KNEW was going away), and ALL TIME would have been rewritten for 30 years of continuity.
There WOULDN'T have been the "everything basically happened the same way" rule where all the basic events of your comics STILL happening. There would have been a full-blown reboot. And that would've affected EVERY book that Spidey was tied into-- and, therefore, the rest of the Marvel U.
Would it have been Peter and Gwen living in Avengers Tower in NEW AVENGERS?
If Norman hadn't "died" on the night Gwen died, would Harry have ever become a Green Goblin?
If Gwen never died, and Harry was cured of his addiction, would HARRY still be dating MJ?
What would have happened to Liz? To baby Normie? Would Foggy Nelson still have dated Liz, the single mother with a kid (baby Normie) over in DAREDEVIL?
I could do this all night.
Let me put it to you this way-- I'm not asking WHICH version of OMD you would have enjoyed more-- I'm asking out of 2 choices, which RESULT would you rather have:
1. 20 years of continuity where "all the events happened the same way, except Peter and MJ were in a committed relationship instead of a marriage."
2. 30 years of continuity being completely re-written with a NEW continuity in place that is DIFFERENT from the 30 years of comics fans had read, starting with Gwen NEVER dying and still being alive all that time, Norman never "dying" and going off the map all those years-- creating a vacuum filled by other characters-- like Harry as a Green Goblin AND Hobgoblin, and so on. Continuity DRASTICALLY changed in ALL the Spidey comics AND all the comics Spidey has tied into SINCE The Night Gwen Stacy (didn't) Die.
If Norman Osborn was never believed dead, how would that have affected the Hobgoblin saga? Should Ned Leeds still be alive? In that case, would Betty Brant still be his wife?
Slott also emphasized why it would have been so difficult to implement JMS's story. It contradicted many stories that had already been commissioned months earlier.
We were working on BND pretty far back in 2007. Remember SPIDER-MAN: SWING SHIFT? That issue, which had teases to BND characters and set-ups, came out the first week of May in '07-- and the last issue of OMD didn't come out till December '07.
We were told all of the story beats of OMD, but we didn't see the specific script for the last issue till we were well into our own run. This is the nature of publishing a 3 times a month book-- and making sure it sticks to a schedule.
For example: Before readers ever saw my 1st story arc with Steve McNiven, Marcos was drawing my 2nd arc, and I was turning in plots for my 3rd arc (NEW WAYS TO DIE). When fans ACTUALLY got to see the issues and voice concerns about Harry's return-- my very NEXT arc addressed it (the Molten Man two-parter).
For most artists, it takes a good month to produce a penciled issue of a comic. That's not factoring in the time it takes to write it before hand, the time the inker and colorist are working on a staggered schedule on the other side of that, and you also have to add all the various editorial issues AND the hard work the letterer and the production department have to do. It's a massive group effort!
Schedule-wise, when you triple THAT for a 3 issue arc (or sextuple it for a 6 issue arc!), the editor CANNOT view THAT as three books coming out in one month, he HAS to treat it as one book that has to be ready 3 months ahead of time, a second book that has to be ready 2 months ahead of time, and a third that has be ready 1 month ahead of time. (Now think about THAT for the 6 parter!!!) AND doing that EVERY MONTH. This kind of scheduling would KILL an ordinary editor-- but Steve Wacker pulls it off!
The plus side: When it all comes together, you get 3 issues a month! (And going by the fan mail, readers frickin' LOVE that-- and want to know why OTHER Marvel comics won't do this.)
The minus side: Once that "train" is on the tracks, it is HARD to make sharp turns. (That's why we created side-projects like AMAZING SPIDER-MAN: EXTRA, so we could address fan concerns-- and OUR concerns-- on a more flexible month-to-month basis.
For example, we got a GREAT reaction on Anti-Venom in NEW WAYS TO DIE. We got lots of requests from fans who wanted to see him again-- right away-- but we were so far into our ASM schedule, we knew he wasn't going to show up for a while. So I wrote an Anti-Venom done-in-one in ASM: EXTRA #2.