~snip~
Two people cannot carry one secret. The secret is not shared. My answer is no.
I think this is the best answer really.
Bitcoin is private property, and whoever has the keys has access to it.
People can change in the future, and even if you think you know someone today, that person might be completely different in a decade for example.
You can be in a really bad situation in the future if you share all your private things with someone else.