I'd argue the TYFU was when you hid information about finances. Or felt the need to do that. Typically that means something is wrong somewhere else.

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Also how would moving the account over show the other party all the information on your personal account's transactions?

when you sign in you should only be able to see information for accounts you have access to/are owner of. Do you see your partner's personal account?

If you do then those aren't personal accounts, they are either joint, or have written authorization to disclose the information to the other party.