at 4:02 he starts firing at 4:04 and stops at 4:08 Most of the shots are body shots. The other player wasn't even shooting back so it's not a surprise that the low level ended up beating him.
I nice test would be if a team went in and actually had a low level take x number of shots at the body and head to see how many shots it took. Then to have the higher level do the same and see how it compares. To be scientific about it instead of going off of everyone's opinion.