Using the rope is a complete cluster-fuck if you've ever done true "long routes". What you save in a few ounces of weight you lose in efficiency and time. Plus, you always climb the next pitch with the mindset that you have to stop early so you have enough rope to complete the anchor. Again, this is less efficient and costs time. Also, cord is a multi-use piece of gear; your climbing rope, not so much, especially when you're tied in. But hey, if you wanna haul around an extra 10M of climbing rope and claim to save weight by not bringing cord and lockers for your anchor, go for it.