Who would be placing those buy orders?

I think a better starting point is a discussion of what extent the Hive Fund should all be converted to HBD, or if a significant portion should be staked as a delegations fund. That fund could then allocate non-voting resources to projects that need to create new accounts, process transactions, and otherwise allow users to use Hive. A bit like how steemit used much of its stake to create new accounts.

I think there is a good argument to be made in favor of delegations. As long as it doesn't carry with it the disincentives that the delegations to projects did on Steem where receivers cared more about min-maxing the earnings from their delegation than actually growing their dApp.

The problem with delegations is, who decides who gets them.
If we decide via the HIVE fund, what happens if delegations need to be adjusted? Some delegatee might go rogue and misuse the delegated stake. (it's unlikely but could happen; Sun using exchanges to overthrow Steem was also unlikely...)

You undelegate them even though the HIVE fund decided who gets the delegation? That's gonna be a PR nightmare... even if they misused the delegated stake.

I don't see why we could not have hive fund delegations if we really wanted to do the development (I'm not exactly in favor for it but hey why not).

Just have a part of the hive tokens be powered up on the sps account, and then add a new kind of proposals where you ask for sp delegations instead of daily HBD. And then do the same system where if you no longer have enough support you lose your delegation.

The system I explain above would work much better as a decentralized community than when we had steemit delegations because we can be more agile and reasons are more clear than when it was behind closed doors.

"Request a delegation" is a good solution to the problem I mentioned. Thanks for your reply.

The only downside is dealing with the 5 day wind down for delegations in some way. Likely making a special delegation rule specifically for sps delegations.

Would it be possible for potential delegates to sign into an agreement where a (vast?) % of the curation rewards go back into the DAO, and/or are burned?

Mmmh "sign" in a trustless way ? That would require some code changes in the way curation rewards are paid out, but could happen yes.

I guess it wouldn't need to be trust-less - don't abide by the rules and your delegation is removed. I think that 'here', folks would abide :)

Well then it's still a bit tricky, because you need to power those rewards down, so it takes 13 weeks to get those rewards powered down to send them back.

True. Well it's something to think about. As the original comment states, we could do with something to de-risk projects with this delegation from using it to prioritize themselves over the growing the network and their app.

I would think that a hardfork would set a price and it would depend on the market when they sold.
I can't see converting it all at once, maybe a powerdown's worth at a time.

I would like to see some of it powered up and put behind cheetah and hivewatchers/cleaners.