When a straight guy is so desperate for action that he succumbs to sexual activities with another man because, as anyone who hit puberty knows, every guy is a horny mother-fucker.
Person A: "Dude, I haven't gotten any poon in almost two years. I'm ready to do something gay by desperation."
Person B: "Dude, I know how you feel. You can crash at my place tonight if you're feeling lonely."
Person A: "Only if I can crash and burn...IN YOUR ASS!"
That definitions is as accurate as could be expected, until he missed the Eagles lyrics. "Out riding fences" is accurate because in those days, any fenced land was obviously protected by the local Sheriff and/or the United StatesArmy. This is not a boundary of trespass that a wanted man would want to risk imposing himself on unless in the most dire circumstances. It say's nothing of mending fences in the song.
A Desperado would not venture on a rancher's fenced land for fear of being hung as a cattle thief.