Shit Happens

Lyrics: Hunter or Barlow?
Music: Weir, Mydland or Hart?

There seem to be two different outtakes from the Grateful Dead's "Built To Last" sessions called "Shit Happens". One is described by Steve Silberman in "Skeleton Key" (though it doesn't circulate so far as I know):

An outtake from the Built To Last sessions that may have become an anthem of the Deadhead fraternity, but never made it out of the studio. A studio rehearsal tape has a take of "Shit Happens" between a slow, fragile version of "Blow Away" and a drum-machine-driven "Foolish Heart." The song's chorus, "Shit happens - that's all we know! Shit happens, and awa-a-yy we go ...," glides on a irrestible hook, and verses are swapped by Weir, Mydland and Lesh, who sings in a barbershop basso.
The lyrics quoted are from the Robert Hunter song Tough Changes.

The second circulates as a filler on what is known as "The Inn By The Sea" tape. It is normally described as "Bob Weir - studio sessions." It consists of the verses below sung twice, with only a drum machine for backing. It's variously described as being either John Perry Barlow or Mickey Hart singing.
It doesn't matter, doesn't matter, it's all right
Universe still works tonight
Shit happens, shit happens, it's OK
What comes to pass will pass away

Whatever hits the fan might splatter
It's all right 'cause it doesn't matter
Doesn't matter, doesn't matter
It's all right, it doesn't matter
These lyrics seem to be based on the John Barlow song It Doesn't Matter, which has the chorus:
It doesn't matter, doesn't matter
It's alright, it's alright
The Universe
Is workin' fine tonight
It doesn't matter, doesn't matter
It's OK
Whatever comes to pass
Will just pass right on away