"the deadlift [...] is not very impressive, [...] and it's not very useful, athletically speaking."
That is probably the most false statement I've ever read on the internet. Which is saying something. Athletically speaking, there is no single exercise better than the deadlift. With the squat coming in at #2.
If you play tennis, box, run 400m, or play basketball, then pursuing a heavy weight deadlift routine is going to compromise your performance. Sometimes it might help build some strength, but beyond a limited amount sinking a lot of training capacity into it is going to slow you down and compromise endurance. This is not remotely controversial.
I know people who were able to dunk in high school as teenagers and were very explosive. Than they started weight lifing regime, lifted hard for a decade (solid weights on compund movements), still can't really dunk no more, while they should be even more explosive.
Thing is, pylometrics is still nr. 1 for most explosivnes and also olimpic lifting, but not classis weight lifting, strength is not power.
+EDIT: This guy on the video does far more than just DL to achive what he does, he is also very competent at calisthenics, he does one leg hill jums and other extremely difficult exercises ... Claiming this is a product of solely DL is misinforming.
That is probably the most false statement I've ever read on the internet. Which is saying something. Athletically speaking, there is no single exercise better than the deadlift. With the squat coming in at #2.