I disagree with you derek, and the intro and bass line for
Lounge Act is exhibit (a) of Krist's original contributions. Here is
milk it Exhibit (b) these are songs that include bass fills and riffs that are not exactly just paralleling the guitar parts.. Also, even when playing the same notes as Kurt, Krist clearly brought a groove, feel, and tempo to the songs which is evident in their evolution from solo guitar on Kurt's demo tapes to finished product on the record and especially in the slight variations evident in differing live performances. The music of Nirvana is built on a dynamic between the three instruments even if gutted and simple.