I'll have a pint of whatever the author was drinking please.
Not the safest manoeuvre. I had one trip on a tanker years ago (ANG KC97 -the one in the Dayton museum btw) everyone wearing a 'chute and considerable briefing beforehand.
One point not mentioned; aircraft departs with minimum fuel load, second aircraft, carrying loads of fuel departs. Highest fuel burn is during take-off so it's just been doubled.
Aircraft could refuel over the North Sea. Yeah, right. OK if there's just one, maybe. But get ten or so trying to do it at the same time in a very busy bit of airspace and ....
Bet the same guy will shortly prove bumble bees can't fly.