That's pretty neat! The concept has been discussed several times before (both on Bitcointalk and on Reddit) as it's probably the most straight forward way to do a dead man's switch in Bitcoin, but it's the first time I see it actually implemented (at least without the necessity of manually creating a raw transaction yourself).
true, but if you are making a 'will' and have the coins in cold storage it's highly likely that you won't spend them.
Everyone needs to spend money to pay for their basic necessities, at a minimum. Those that are most likely to die, those in retirement, will need to spend down the money they intend to pass on to their heirs.
Not that much of an issue if you have separate accounts for daily spending and long term savings. Creating a new "insurance transaction" every few months when you refill your daily spending account doesn't sound that bad.
What alternative do you propose? Leave the private key encrypted with the heir PGP private key somewhere in the house, to be found when you die?
Well, one can always keep their seed phrase in a safe deposit box (made accessible after your death), with a passphrase passed on via a separate channel (e.g. a notary executing your will, separate safe deposit box). Involves third parties which makes it less fun, but maybe more practical while still reasonable secure for most people.
Alternatively -- just to put it out there -- make your last will a scavenger hunt for your seed phrase. Something out of Indiana Jones.
Or Saw, depending on how well you like your relatives.
