That district was drawn by Republicans not "for John Murtha" at all but for the purposes of:
1. Putting 2 Rat incumbents (John Murtha and Frank Mascara) into one district while eliminating the old 20th district entirely, and
2. Jamming enough Rat voters into that new 12th district to shore up Republicans in the adjacent 4th and 18th districts (we also added more Rats to the 14th district, which also helped the 4th & 18th).
Republicans will control the process again this decade, and it looks like we need to get even MORE help into the 4th district to exterminate Weasel Altmire (and more into the 12th to screw Critz), while not endangering the 18th. It can be done, but the result might look even more like an out-of-control jigsaw puzzle piece.
My district (the 18th) is so heavilly conservative that we could probably absorb the rest of the Mon Valley without any lasting damage. Ditto for Johnstown and the adjacent conservative trending districts.
OTOH, Pittsburgh itself is still shedding population and can easily add the remaining most leftwing suburbs such as Wilkinsburg. These changes would make less, not more, gerrymandered districts.