I had a very original '72 Superlight that was 58cm c-t. With the yellow label Fiamme's and a corn-cob FW it weighed an honest 20lbs.
It's pretty tough to go sub 20lb. without going to an alloy FW and ti BB. Remember most people at the time that thought they were riding 20lb. bikes were most likely on 22-24lb. bikes.
Drillium is not really about the weight, it's about the cool. And the attention to detail that one puts into their build. And if you are careful about ALL the details: keeping cable housings and wires to a minimum length, trimming excess threads off through bolts, trimming handlebar ends, etc. it does add up to a minor weight savings. But to me it's more about the pride I take in a carefully set up build.