Moving a keychain item results in corruption

In older versions of macOS (such as Snow Leopard and earlier) we used to use Keychain Access to create new keychains and drag n drop keychain items between our created keychains at will.

Now with ElCapitan if we attempt to drag a keychain item (specifically an encrypted disk image password which has been saved to the login keychain) the result is the corruption of the keychain item.

I have reproduced this in a fresh user account and even on a fresh OS install on an empty test volume.

So either this is bug or... I don't know what???

Can anyone else reproduce this?