Interesting point - I always thought it was like Korean cursive/script than block Hangul, but never really looked at it. This is the first time I've heard of HiNative. Perhaps I can use them to figure out one of the notations is on the KBS Character chart - again, the notations appear" hand-written" rather than "typed".
When TM and TH were at the art gallery in an early episode, TM said that if he hadn't been born into Taesan, hemight have become an artist like TH's mother. TH replied" That's why Mom liked you alot. It almost made me jealous" At the end of the convo, TM said "Let's try to get along. . .". It was a very nice scene. And, of course, there have been several other references to TM's love of art.
Thanks for the info.