The bane of Astros fans for the last five years has been the Bullpen, or the Goatpen as we not-terribly-affectionately called them.
The 2014 Astros bullpen posted an even 0.0 WAR, 4th-worst in baseball. The 2013 Goatpen posted an unbelievable -5.6 WAR, worst in baseball by...yeah, 5.6 WAR. Cumulatively from 2010-2014, the Astros' bullpen was "worth" -3.6 WAR, worst in baseball by 8.0 WAR and the only bullpen to be worth below replacement value.
So when the Astros brought in Pat Neshek and Luke Gregerson, we fans expected some improvement. I don't know that we expected this much improvement, however.