Both ignorance and stupidity are potentially lethal. Not knowing stuff is normal ignorance and can be easily fixed by education but nothing can fix stupidity. Of the four serious tree stand accidents I know anything about, common stupidity has been the sad common thread.
Ignorant or foolish, I especially hate to hear that someone has been injured or killed while misusing a tree stand and my heart goes out to the mourning survivors. But, I can't help but suspect that it was only a matter of time before something truly painful would happen to the victim.