Or, he could be advocating the most agile process that the technology of the time (1970) would allow. Remember that there were no desktop computers, no internet, the programming language C was just being created.
Agile processes don't depend on technology, just people, paper and communication, in fact technology can be a burden sometimes.
Just in case someone from the future misunderstands this: I don't mean that agile drops analysis, documentation, planning or monitoring (they are essential to it) but it leaves the "intensive" and "before" parts out.
Development processes very similar to todays "agile" family, existed back in 1970. "Evolutionary prototyping" for example (a member of the "prototyping" process-family), is one of the precursors for todays agile practices.
