I watched the video, but it is all just bs really.
I think one have to look at mining as a way to distribute coins and more as a market function than "cost per transactions" and "kw per transactions".
When you strip away the incentive to get coins from mining, you could currently run the entire bitcoin on one low end PC, the database and transactions processing etc.
So when you don't get any more new coins the mining, then the cost of transactions becomes apparent.