[CQ-Contest] "Back in the day" -- Single- or Multi-op?

[Art Boyars]

On the N1MM+ reflector somebody wrote:

"For those of us who have been around amateur contesting a while (1966
here), you probably called the assistant who listens to the QSO and records
the QSO details a "logger."  A single-op station could usually have one and
sometimes more, but none of them was allowed to transmit; doing so made the
entry Multi-Op."

I never heard of such a thing.  I would have thought that having a "logger"
made you multi-op.

Can anybody here on CQ-Contest provide reliable info on the matter?

73, Art K3KU
Contesting since a little earlier than 1966