I want to be absolutely clear about this because for about a fortnight I believed my grandmother had built a fortress and she had not.

A customer cannot place a legally binding instruction like that on her own account.

It does not create a second signature requirement.

It does not freeze anything.

It cannot bind a teller, and it certainly cannot bind the bank after her death.

It is a note in a file.

What it does do — and this is the whole of it, this is the entire mechanism of this story — is that somebody at that branch typed a line into the account’s comment field.

So that when a teller opened Margaret Henderson’s record on a screen, a box appeared that said: