> The system developed by Bell Labs, troff, was as different [from SGML] as could be: a direct typesetter with no imposed structure ... Actually, the point of

> The system developed by Bell Labs, troff, was as different [from SGML] as could be: a direct typesetter with no imposed structure ... Actually, the point of SGML's tag omission, content model, and shortform/alternate syntax features is to infer a document hierarchy from a flat, printer instruction representation. Though I'm not aware this has ever been applied to troff/nroff. James Clark should know, as not only did he develop the SGML reference implementation (SP/OpenSP) but also groff.