1) Go forth- levis borrowed the poem "Go Forth" from Charles Bukowski. Which it is really called "the Laughing Heart".
2)It could be considered ironic it is promoted by Levi but now it now talks about living on the edge. Being free. Living with no regrets.
3)Yes it does reflect repatition  of the author because it is written so well and keeps the reader in tune. It is short but strong and well laid out and on point.
4)Just wrote "Go Forth" on Google which led me to some images of the poem then led me too YouTube and that old guy popped up with "the Laughing Heart"