He has the right idea, but his terminology is a bit mixed up. Nitrous doesn't add 'boost' to a car. It adds cylinder pressure when it fires because of the increased oxygen content (in the nitrous oxide). Boosting adds more oxygen and therefore more cylinder pressure mechanically by adding more air.
Also he says that boosting will burn pistons but nitrous will blow them up???? Both boosting and nitrous can melt pistons by the same method - which is running lean. Nitrous tends to do it alot faster than a turbo will. Both problems derive from lack of fuel, or in a turbo's case, preignition from hotter air.
There are better much explainations of the whole Nitrous vs Boosting issue than the one you linked to.
