Once Lawrence Tynes was healthy enough, it seemed like the Giants were waiting for Carney to falter, so they could have an excuse to replace him. At this point, it seems like one bad game should not be enough to make that decision. It is nice to have these problems.
Lastly, although Mike Tomlin claimed no team has a back up long snapper, he may be mistaken. If Zak DeOssie were to be injured (punching myself for writing that), Grey Reugamer or Jay Alford both could sub for DeOssie, and have experience in that area.
Post lastly - Tom Coughlin said in his conference call that if a kicker were to go down mid game, that Chase Blackburn could be called upon to kick. He then noted, that it was more likely that either Jeff Feagles or Carney would be called into action instead. The thought of Blackburn punting, or place kicking, is both terrifying and hilarious all at the same time.