If there is one thing that baseball fans (and most humans) are guilty of, it's recency bias. "What have you done for me lately?" is a pretty common sentiment, especially for Yankees fans. That is why Brandon McCarthy is considered an upper-tier starter given his short stint, for example, and it is certainly why Stephen Drew is considered a scrub.
This isn't to say that Drew is great or anything (and it isn't to say that McCarthy is bad!), but I think it's important to look at the larger picture. Firstly, Drew is a wildly inconsistent player, only posting consecutive 2.0+ fWAR once (2009 & 2010) and consecutive 1.5+ fWAR seasons from 2008 to 2011. Since 2011, he's had one good season in 2013, and that was largely fueled by an uncharacteristic BABIP.
Nonetheless, there is no way that Drew is the 44 wRC+ hitter that we saw in 2014, and that's what he sorely needs to avoid. If we look at the projections, they clearly factor that poor year into the equation but also consider the more distant past:
|AVG/OBP/SLG||Defensive Runs Above Average||WAR/WARP|
|PECOTA||.230/.303/.370||SS -3, 2B -1||0.7|
All of these projections are in roughly 350-450 plate appearances, so it's not a total flop. If he manages to put up what is a half-season of close-to-average play at second base, then I think we should be thrilled.
There's always the possibility that his talent level has just fallen off a cliff, but there's no way to know that for sure. Drew was acquired as Rob Refsnyder insurance, and rightfully so. While he is definitely ready offensively speaking, the Yankees would love for him to spend a bit more time polishing his defense at Triple-A.
That doesn't even include the fact that if the Yankees really think Refsnyder is valuable, then there's no reason to call him up to start the season. This would essentially eliminate one year of team control, so the team will likely hold him down until after the Super 2 deadline. So while Drew seems to be a costly endeavor, it would pay some dividends if it means that the Yankees gain another pre-arbitration year in Refnsyder.
We reached a serious low point at second base when Brian Roberts' ghost tried to man the position, and he hit a lowly 84 wRC+ with pretty poor defense. If Drew hits that exact same offensive mark but with better defense, then it would be a slight but marked improvement.
This doesn't mean that he should perform this way the whole season, but it does mean that he needs to at least hold down the fort until Refsnyder is called up. If he can put up nearly a win and then serve as a utility infielder, he will have adequately served his purpose. While expectations are rightfully low and he is not a star, Stephen Drew merely playing to his projections would prove decent enough in what many of us hope to be limited playing time this season. After seeing the infields of 2013 and 2014, that's a big step up.