It's 2018 and everything flying commercial is well sub-sonic. 12 hours in any ally tube is at least 8 hours too long for anybody. Is this a Big Bubba/Airslush strategy to keep more tubes in the air for longer, justifying higher prices and forcing people to upscale in comfort levels in order to avoid DVT or worse. (Think how many ambulances will be required to attend after pax have been incarcerated for 20 hours) Current aircraft are just all so last century. (Concorde excepted). I predict than the first manufacturer to get an economical SST to market will kill off the rest of the competition.
"Just stating the bleeding obvious but I feel better now"
There are dozens of DVT cases every year following long hauls. Nobody seemingly thinks seriously about it / wont happen to them....
One a month dies from DVT at Heathrow | Daily Mail Onlinel
https://www.telegraph.co.uk/news/hea...ur-flight.html