I really just wish they had put some sort of disclaimer in their video about their math trickery. As a current math major who's done some work with infinite series, I was skeptical of their claim that (-1)^n converges to 1/2 and so just ended up being confused when they said that the sum of all natural numbers converging to -1/12 was consistent with modern physics. Now, a while after seeing the video I decided to do my own research and came upon this article which was very helpful in understanding what was actually going on. I suppose I have a different perspective on math than the average person, but I was much more satisfied with this, correct explanation, than their hand-wavy one.