dave knudson has his own way of playing guitar, its rad... anyways he uses finger taps 
hammer ons for this...

e:---------------------------|
B:-----h19----h17-----h15----|
G:--h7------h9-----h11-------|
D:h5------h7-----h9----------|
A:---------------------------|
E:---------------------------|

umm use the hand you form chords with to do the hammers on d and g, and then use your 
hand to hammer the notes on b...

if you see them live, this man has like 20 different pedals so it might sound a little 
but this is what i remember him doing... work with it and hopefully it will progress into 
full tab...

you can send me questions or comments at icepot (at) comcast (dot) net.