I've been complaining about the St. Louis Cardinals' handling of their shortstop situation since a recurrence of Rafael Furcal's elbow injury was just really likely, instead of actually true, and I'll probably keep complaining as things continue lurching forward. So please, allow me to take this moment to say that yes, the Cardinals have succeeded with less-than-stellar middle infielders before, and they could well succeed with less-than-stellar middle infielders in 2013.
Some recent, less-than-stellar examples:
Ryan Theriot, 2011
In 2011, the St. Louis Cardinals won the World Series with Ryan Theriot making 87 starts at shortstop. It was what it was. That year Cardinals shortstops hit .264/.325/.363, which actually wasn't so bad, but Theriot's defense was
and the way the Cardinals finally solved the problem was trading a newly awake sleeper-prospect (Alex Castellanos) for Rafael Furcal, who hit .255/.316/.418 and didn't roll so many baseballs to second base like a kid cheating at mini-golf.
Skip Schumaker, 2010
In 2009 the Cardinals managed to stabilize their middle infield without selecting a single stable middle infielder--Brendan Ryan revealed his absurd defensive abilities and also hit .292, and Skip Schumaker moved to second base and proved hitting and fielding like an outfielder was a viable business model there.
In 2010, though, Schumaker hit like a second baseman and fielded like an outfielder, and that isn't especially effective; rWAR has him well below replacement level, which makes intuitive sense. But those Cardinals missed the postseason by more games than a league-average second baseman would have won them, and missed their Pythag by the games that would have caught the Cincinnati Reds.
The Cardinals didn't have much backing up Schumaker in 2010, unfortunately; Aaron Miles hit the emptiest .281 (.311/.317) imaginable, and Felipe Lopez stopped hitting, too. Of course, the Cardinals went back to the well in 2011, and were treated to a slightly less disastrous season.
So, yes: Sometimes you can drag Ryan Theriot to the World Series, and sometimes Skip Schumaker isn't what's keeping you out of the postseason. It's worth dropping a little perspective in while we wait for another excuse to wonder about the Cardinals' shortstop plans in 2013.