Proteus was at the early end of the American frame building
renaissance (for lack of a better word.)

I went to the University of Maryland, College Park, and the shop
was nearby. I never got the bucks together to buy anything
better than a second hand UO-8, but certainly was intrigued
by the concept of building your own high performance frame.

I have no idea of the quality or alignment of their production
frames, because i have no experience with them, but it would
not surprise me if they turned out both good and bad stuff,
because like I said, that was pretty early on in the learning
curve here in the USofA.

Besides custom frames, IIRC they would sell you tube sets and
lugs/dropouts.........bike in a box that needed a lot more than
handlebars turned and pedals mounted.

Jesus, I just looked at Mudboy's link and I think I'm having a
flashback. Did we really look like that?