He may have meant that fireman did not have a "brief" this was a Traffic
Branch exam that Signalman, Guards etc had to pass before they could
operate over a system. Drivers and Fireman were in the Rolling Stock
(later Operations) branch and were not required to pass these exams. Of
course the Rolling Stock branch had their own exams which went into each
safeworking system in detail.
Mark.
Some people make art to impress others.
I make art to impress myself.