It's honestly the only way I can get through to BND. Looking at MJ as the one making this choice helps. A lot, actually. Because otherwise, it will only make me think of Peter as a complete idiot. Which is funny, because JMS's Peter is the only Peter I really "liked." Before, it was the character of Spider-Man I couldn't wait to see, but JMS made peter more likable for me.
I agree that if it's both Peter AND Mary Jane who make this decision together (and it looks like according to the CBG they will) it's not nearly as bad. However, it's still bad because:
1. A lot of folks guessed something like this would happen. Sort of like the Other. Not many knew the fine details but everybody guessed the action line.
2. It completely screws up a lot of continuity. For example, if [BLACKOUT]Peter never married MJ[/BLACKOUT] then he should still be wearing the black costume from time to time, because the only reason he stopped wearing it was because it reminded MJ of Venom, who went to her specifically to intimidate her because she was Peter's wife. But if she never was, then Venom would never have gone there.
It gets better. The unmasking will be erased (yay!) because, since Peter made his decision to reveal his identity based on his family asking him to, and since he'll [BLACKOUT]never have married MJ[/BLACKOUT] and therefore his reason to ultimately unmask will be null and void. However, this completely screws up Civil War because a good portion of that story revolves around Spidey having a public ID, which means portions of his will be cut out. This also includes Aunt May getting sniped (which also means all of Back in Black is gone). But if Spidey never revealed his identity, then Spidey wouldn't have left Stark Tower, and the Kingpin wouldn't have put the hit out on Spidey, which means Aunt May would never have been shot, which means she wouldn't be close to death, which means Spidey would not have been forced to [blackout]choose between Aunt May's life and his marriage to Mary Jane.[/BLACKOUT] Thus we have ourselves a paradox not unlike the time traveler going back in time and killing his/her own grandfather/grandmother, thus never existing, and thus never going back in time, and thus the grandfather still being alive.
Or how about the clone saga, which will be even more convoluted. That's because a good portion of it revolved around Peter and MJ being married. [BLACKOUT]But if they were never married[/BLACKOUT], then Baby May would never have been conceived, and since the complications to her pregnancy was the reason why Peter and Ben tested themselves to see who was the clone, since it was feared that if Peter was the clone, that was why MJ's unborn child was in danger. So how did they resolve who was the original this time around. Also, the Green Goblin would not have got involved with the "miscarriage," which means Peter would not have gone to find his daughter, which means he never would have found the real Aunt May, which means he would still think Aunt May is dead, which means she wouldn't be on death's door this time around, and so the paradox begins again.
The only good thing out of this partial erasure it seems is that MJ will no longer be a guilt-ridden liar concerning Gwen and Norman's mutant ninja kids, although technically they would still exist and MJ wouldn't have been there to stop Peter from being macked on by Sarah and Peter wouldn't feel so guilty because he's not cheating on his wife since he's not married, so I guess, technically he's a pedophile with necrophiliac tendencies considering that Sarah is in reality ten years old and looks exactly like her mom. Anyone still think this move doesn't open a whole bunches of cans of worms?
3. Any relationship Peter gets involved in from now on with any woman, including Mary Jane, is pointless because, since we all know he can't be married, then any relationship he has is doomed to fail, so why should readers be emotionally invested in soap opera style love triangles.
4. It's just another instance in which Mary Jane is the scapegoat for what Marvel believes is the problem with Spider-Man when all they have to do is look in the mirror.