Reading this made up my mind that I am a true INTP (I always score close to 50/50 between P and J - I'm soothed by order/organization/planning and intensely desire it, but have problems implementing it myself). My parents could have written this, including most of the examples of individual kids.
The only thing that isn't EXACTLY me is the tendency towards risky behavior until learning for yourself the consequences. I'm super-cautious and reserved in every arena. Detest (as in it bothers me to see anyone doing things I feel have a good chance of getting them hurt) and avoid all kinds of risky behavior, and despite being hyperactive and curious I almost never got physically hurt even as a baby/toddler. Guess this is my J coming out?