Usually, it helps to consider the context, rather than to deconstruct what is obviously a poorly worded statement.
The only way is it "obviously a poorly worded statement," is if you assume it to be one.
It makes every bit as much sense to read it as I did, and, considering the wide variation in performance often seen among relievers from one year to the next, and the fact that the 2013 Cubs are not going to be contending, it is also an approach which would make more sense than spending heavily on relievers this winter. Two of the three relievers he mentioned having done well in 2012 (Camp and Russell) were little more than arms thrown into the mix, without a great deal of certainty they would come close to doing as well as they did. Before 2012, Russell had never had a major league season with an ERA as good as the league average, and he had not exactly dominated in the minors, and Camp was entering the season as a 36 year old who had an ERA of 4.21 in 2011.
Those are NOT "good arms" when they were seen as possible relievers for 2012. They were part of a collection of arms offered to Sveum to sort thru.
I would guess that the principal difference for 2013 will be that there will be even more of them for him to sort thru for 2013.
I look at the wording, look at the situation, and look at the track record (those things you might call context) and take it to mean they will look to add a "good number of arms."
You call that "deconstructing."
You look at the wording, project on it what it seems you would like it to mean, and truly ignore the context, and take it to mean the Cubs will look to add "a number of good arms.
I call that wishful thinking.