the other guy looks weird moving.
That kick is not permited in sparring in the gym I´m at. High kicks are permited. Hook kicks don´t even get mentioned but yep, I mean spining back fist is banned, front kick to the face, knee to the face, I wouldn´t eve think of hook kicking. Thing is if it´s a lot of members you can´t count on every single person being reasonable, need bullet proof rules. Spinning back to the head is banned obviously too. We can actually head kick with roundhouses.
I want front kicks permited but I understand not everyone can control them well. Then eventually you would have some guy do them in a bad way and cut someone face with it. Before I knew about the rule I did throw it once. Even got like a praise nod for it. Not by the trainer just the guy I kicked.
However I rarely do throw hook kicks on a bag practicing. Hook kicks are solid to have as a "rare" technique to catch of suprise. A heel is a very hard body part and the kick doesn´t have to be extraordinary to hurt.
Here is a good example of it