I had the SS as my relief F/O on a HKG-YVR At the end of my 5 hours rest I returned to the flightdeck to find that NEITHER of the two F/Es would speak to him and the other F/O (ex Lightnings) had decided to "keep his council" On the return trip he was PF into TPE at night and had to be "helped" around the visual approach to avoid a go-around.
A few days later I was summoned to see the Fleet Captain to explain why I had been showing the SS some operational documentation from a previous airline - and I was told to desist!
So, my impression was that he was a bit of a politician and a man in a hurry to rise up the hierarchy - which he did of course.