Look at what you're saying....
No Injuries. Everybody has injuries. Tyhat's why you have a bench. To go through a season without losing an important player for a significant amount of time is unusual.
If pitching is good. We have two healthy, proven, major league starters. Niese, and even he has a heart condition. Our crack medical staff says it isn't serious, but when's the last time they've been right? Marcum, who's getting old and wasn't more than a decent # 3 anyway. Santana's arm is attached with duct tape. Gee is coming back from a serious medical problem. Who knows what he'll be? Who knows what Harvey is too. If anyone can't pitch for an extended period, or busts, we have very little to replace them with. To have good pitching would require each of them to pitch as well as they ever did, all at the same time. Very unlikely. Santana holding up all year is unlikely too.
BP is much improved. Why should it be? We signed a few guys off the scrap heap. If any of them work out, more luck. Different names, same thin talent. I do think Francisco will be better, but he could hardly be worse.
No prolonged slumps. Slumps are part of the game. If a player goes through a year without one, he has a career year. Those are rare. For everyone to have one the same year is lottery winning luck.
One of the outfielders break out. Cowgill and the others have been knocking around for years. There is a reason they're part time players. Our own crop of wannabees showed why. Kirk N looked good, but was exposed when pitchers discovered his weaknesses. We have a bunch of backups, at best, in the OF. COULD one of them put it all together? Sure, but unlikely. It would require a lot of luck.
Duda, Ike, David and Murphy have normal years. Well, normal is what you can expect, so that's not asking for much. However, normal for Duda is he'll stink. Normal for Ike is he'll look great for half a year and either stink or be injured for the other half. Davis is an all star and I expect him to remsin so. Normal for Murphy is being a deeply flawed player who will hit well, but has no range and can't catch much of what he does reach in the field. What you're asking is that Wright continues to shine, while Duda, Murphy, and Ike play as well as they did for parts of seasons for the whole year...have career years. Not too likely.
So sure, IF all that happens we can be good. If bad players suddenly play better, we can be better. Sure, you're right...and it doesn't require the violation of any laws of physics, so it's possible...but don't you see it requires mountains of luck? If all that happened on another team, the Pirates could play the Royals in the WS. What are the odds of that?