The Knights mentioned his work with Aku Uate, and I mentioned it earlier in the thread, but I think it's worth saying exactly what he achieved with Aku.
When Sandercock came to the club Aku had played maybe half a dozen games of firstgrade over 2 years and had a reputation for making massive stuff ups on the field. He was a 6'4" 105kg Fijian who could run 100 metres in sub 11 seconds, but you'd hold your breath any time a kick or a play went his way, because he could do anything. He had the shyness common to Melanesians and had learnt English only a few years before and could barely read and write.
Sandercock was able to use his communication skills from his time as a school teacher to teach Aku all the things that no one else had been able to get across to him over his four years in the Knights system, and almost immediately Aku became a regular firstgrader and finished the season as top tryscorer in the NRL and Dally M winger of the year. In his second year under Sandercock he is pretty much undisputed best winger in the world. Admittedly, Aku has more God given gifts than any player i've ever seen - he hits the line like a prop and is the fastest player in the NRL - but he was a poor reserve grader two years ago.