It seems almost impossible that he could achieve his skill with 2-3 hours per day of practice 'after school.' I cannot possibly believe that Xuanyi Geng mastered ZB at age 7-8 with 2-3h/day of practice, and Tymon (if I'm not mistaken) says he practices for 8 hours per day at least, which seems more realistic. However, reaching sub-10, 4 months after learning OLL/PLL (as explained in the video), certainly shows immense natural talent, most people take over a year (in the best case), to reach that.