I've read that Ji Chang-wook does his own stunts. It's one thing if a scene with stunts can be shot in one take, but I can't even imagine having to shoot multiple takes. He also said he welcomed his newest project "Suspicious Partner" which didn't required demanding stunts.
"Healer" was one of my favorites too, but I've only watched once. One my my favorites was "Smile, Dong-hae" (2010), which has a whopping 159 episodes, and I've actually watched that twice! It's here on Viki too:
I've managed to watch all his dramas with the exception of two or three. I only watch on sites with licensed content and I've never been able to find ""My Too Perfect Sons". And I have "Warrior Baek Dong-soo" on my list to watch. I haven't seen any of his movies but the newest "Fabricated City" sounds interesting.
Hope he's doing well in the military.