I don't have to read the article to know it's a flawed concept, like every previous iterations.

Require trust that the creator properly generated the key and didn't keep a copy then you need to trust that the tamper resistance of every intermediaries. Beside checking amounts there could be nothing in there until you break the seal.

The closest thing you can get to physically moving bitcoin off-chain are with OpenDimes. https://opendime.com/

Here's a similar article from someone who bothered to promote his content outside of steem : https://steemit.com/bitcoin/@styletokill/bitcoin-smart-banknotes-launched-in-singapore