Yes, in Florida, a person named as a POD beneficiary can also serve as an attorney-in-fact. The critical point is raised in your second post, can the attorney-in-fact appoint himself as a POD beneficiary?
Florida law is pretty clear on this with a durable POA:
(b) Notwithstanding the provisions of this section, an attorney in fact may not:
[abridged]
5. Create, amend, modify, or revoke any document or other disposition effective at the principal's death or transfer assets to an existing trust created by the principal unless expressly authorized by the power of attorney;
If it's not a durable POA, it cannot be done. If it's a durable POA and it explicitly grants the authority, it can be done. Nothing is assumed.
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