Yes the ropes need to extend a ways from the boat. Trial and error will show what will work best for you. The more wind the more chance of the anchor slipping and a longer rope will stop the dragging anchor. The back anchor rope's length isn't as critical but if too short the anchor can bob up and down and mess up you precision anchoring. You don't want either anchor in the brush pile, more like several yards on either side of the brush pile.