Good summary, and the right question to put on the table. You are right that all five cases lean on retention; mine certainly does, since a flow only recurs on footprint the DAO still owns.
My answer: under a metered flow the retained-share question partly dissolves. The DAO never alienates the stock, so retention is 100% by construction, and what actually needs deciding is the release rate: how much use is out on lease at any moment, and on what terms. Governance can turn that dial every period instead of having to get one split right forever. A one-time percentage is only the natural frame if you assume sales. Drop the assumption and the decision becomes recurring and reversible, which is a better shape for a choice this large. RAMTIME’s high bar for alienation fits inside that frame; I would go a step further and make the default that there is nothing to alienate, only terms to set.
The Harbour Industrial piece makes the same dependency visible from the investor side. Their buy-back produces a recurring bid only while a recurring stream funds it, and only retained footprint yields one indefinitely. One detail in their text is worth pausing on: proceeds “denominated in DOT, or converted to DOT if denominated in dotUSD”. That conversion leg is an extra mechanism someone has to build and keep running. Settle in DOT and the bid is structural from the first block.
One firewall so the threads stay clean: the wish in the funding thread fixes the settlement unit only. Co-sponsoring it commits nobody on retention. That decision belongs here, and it should get its own referendum when it is ready.