Devereux has been Commandant of the Fleet Officer Training Academy for four years and was, before that, a training officer for eleven. The career path is unusual — most officers who could hold the Commandant's posting have spent time in operational commands, building the breadth of experience they later pass on. Devereux has spent the large majority of his commissioned service inside the training system, on the grounds that instruction is a discipline in its own right rather than a secondary consequence of having been elsewhere.
He was a middling officer cadet. He will say so if asked. The middle of the Academy class, he has said in various forms of the same address given to incoming cohorts, is where most of the Fleet's working officers come from — which is worth bearing in mind when the cohort at either end assumes the ranking reflects something permanent. The cadets who remember this tend to be the ones from the middle.
The callsign was given to him by his own intake cohort before he became an instructor. It has followed him long enough that no one remembers the specific incident it referred to, if there was one. Devereux does not elaborate.