> You might trust that 3rd party now, but not in a years time (when, hopefully, you're still alive)
Then you don't want blockchain-based technology. Remember, the data is still on the chain, and can never be deleted - the paper is pretty clear about it.
So in a year's time if the 3rd party contacts the archeologist, they can arrange to truncate the chain and unseal the key. Yes, the archeologist is not going to get paid on-chain by the protocol, but the secret is still out.
Really looks like the bank's safe deposit is a much better solution if your data is valuable.
