Thanks for the definitive knowledge from someone who is obviously an experienced professional, unterhausen.
I don't pretend to have anything that approches the authoritative knowledge of a pro, and readily confess my own knowledge about frame/forkbuilding could frankly and practically be limited to what I've read in a book.
My late father was a top-notch machinist, trained machine-tool-bulder (ever hear of Walrich?), and very sucessful tool-and-die man for most of his life, so I continue to be fascinated with any precision metalwork, especialy the kind that sucessfully employs skills only achieved over decades of patient experience.