Like most NU recruits as of late, Murtha came in with lots of stars (4) next to his Rivals profile (plus a spot on the Rivals 100) and has underachieved. He was originally committed to Minnesota in his home state, but got freaked out when they took him to a titty bar on his official visit and ended up inking with the Nubbs. He was a big coup in Schnellahan's first abreviated recruiting class made up of the likes of "Psycho" Panico and "Broadway" Beau Davis (along with 2 other QB's with no other offers who ate up scholarships for a few years).
As Callahan's recruiting goes, Murtha's "return on stars" (copywritten by me just now) was probably better than most...but that's saying very little. He has started off and on throughout his career and has shown flashes of being decent and flashes of being pretty poor. I'm sure they have another floundering 4 star kid to throw in there as an underachieving replacement.