Wader:
Concur that crews often did each others' tasks routinely. It was not unknown for the TACO to sit on the spar by the captain's box with the controller in the "B" seat, the senior operator controlling and the junior operator handling the sensors from "A". However, I do not remember learning how to optimise the sensors on the OCU course prior to joining a crew - mind you, that is over 25 years ago and age is a great leveller......and I didn't remember much from the course at the time!
As an afterthought - I came from a crew of mostly smokers, and our non-smoker used to bag the "C" seat whenever possible so that he could curtain himself away from the rest of us! Oh the joys of chain smoking through 8 hours of voicetel, with the paper cup of water slowly filling with tab ends as you lit your next from the stub of the last. "Mandate Moonbeam, this is.... new track...."