Because hitting a board is different than hitting a person.
You're forgetting that there's practical uses for the gi versions of the ezekiel choke and the gi version of uchi mata. The kata/traditional version of the reverse punch will get you killed in a fist fight because it leaves your face wide open.
Yeah, that's called a stylistic difference between boxers. We're talking about karateka being trained one way in kata, and then supposedly trained a different way in sparring.
how is hitting board different from hitting a person other than how it feels on your foot?
"Boards dont hit back?"
Right, which is why white belts learn to set things up.
Is the technique of a throw or sub 100% diiferent on a dummy? c'mon now
and dropping your hand to your waist in a boxing match wont?
thats ridiculous and you know it.
the punch isnt whats different, the set up is.
Cant be any clearer than that.
The stance and chamber are the set up, not the reverse punch.
its that simple. You can throw a reverse punch on the shoulder if you want.