That’s totally true when you’re dealing with the custodian and the custodian alone. However people still have lives outside of Nu are subject to legal jurisdictions and all that scary stuff…
I guess the scenario I’m trying to wrap my head around is when we grant a long-time and well-trusted custodian member a large number of NBT (for example, when we did for BhCnQrYrA5LZm871dtMQEXeU93gmqbhdrC, let’s pretend that wasn’t a multi-signature account, or that both signers are in the same legal jurisdiction or otherwise related).
For a few million dollars worth of NBT, if the custodian were to be sued or their spouse were to try to treat the digital currency assets as marital assets subject to a split, I suspect that an aggressive legal team would try to do quite a bit of hoop jumping to try to get their hands on the funds – and their recourse is “hand it over or you’re in contempt of court, so you go sit in jail”… 
In short, I’m saying we can trust the custodian, and rightfully so, and still end up in a bind due to the fact that people have real lives…
I think we’re all in agreement that this is a very unlikely situation, however given the fact that it is possible, I’m hoping people smarter than me can either:
a) Explain why this is easy to fix,
b) Explain how this is easy to prevent, or
c) Explain how this actually isn’t possible, and I should take off my tin-foil hat: it’s all going to be OK.
I’m just not really all that comfortable with relying solely on the fact that it’s unlikely. Know what I mean?