Ron, are you still talking about arborist rope? The rope IS spliceable on both ends. There is a risk, though. If you think about how the friction hitch reacts on the rope, if you were to descend 60' out of a tree on a 120' rope, when you got to the end, your friction hitch would have milked 120' worth of slack and sent it into the splice on the tail end. You know that splice is a delicately balanced act of tension, and now you messing with all that, risking loosening the splice, and you can figure out what happens next.
love
nick