Nervex pros of course go back a long way. They were actually more or less designed to be a labor-saving alternative to hand cutting fancy lugs. They still require quite a bit of clean up and file work to look really, really nice - something Schwinn never did. There were cast lugs at the time - Hetchins used some on at least one of their fancy-lugged models, but most lugs were stamped ("pressed" being the more common term) and required considerable hand work. The Nervex Pros were considered to be of high quality at the time - and were put to good use on high-end models by a number of builders, Masi and Flying Scot providing some very nice examples. Cast lugs really started to come into greater use in the 70's - Albert Eisentraut had his own design made for his use. But they only really proliferated when Microfusione started really cranking them out in the 80's, and everybody had a set made up with their own name and logos cast in. The vast majority of the lugs of the post-war era into the 80's were pressed and had to be worked by hand - only in the 80's and beyond did cast lugs become the "industry standard."

http://www.classiclightweights.co.uk...ts/nervex.html

Edit to note that in the immediate post-war era in the UK at least, cast lugs were common, and were superseded by stamped/pressed lugs in the mid-50's. They were of course very different from the precision castings that became available from Microfusione and others in the late 70's-80's.