The usual benchmark for the extent to which Gwok Jing's martial arts improved during the thirteen years between the end of LOCH and the beginning of ROCH is his performance against Greats-level opponents. At the end of LOCH, Gwok Jing was barely able to last 300 strokes against one Great using only 70% capacity against him; by the beginning of ROCH, Gwok Jing was able to equal or even slightly surpass a Great.
In terms of actual feats (aside from how well he did against Greats-level opponents), however, was there anything that demonstrated that his martial arts had improved significantly from their level the end of LOCH?