Putting HBD into savings gives a better return and in addition is less a hassle than curating content with Hive Power.
I can't disagree with this statement, although I might add that anyone (with lots of HP) who views curating content a hassle, shouldn't manually curate content at all. If they want to support the community, they can set auto-votes on their favorite authors, and spend their time on "X" or Facebook, posting for free. Curators and long time bloggers here are in it for something more than just a financial investment. I've said for a long time, "came for the crypto, stayed for the community". Really, any long-timer would have sold all their HIVE when it was $3.00, if it was strictly as an investment.
The advantage I see in 20% HBD savings interest is that if HIVE goes very low, investors (if they so choose) can easily divest some of that HBD and put some buy pressure on HIVE to help it go back up. The more HBD they have sitting around, the more HIVE they can buy. Keyword there is "EASILY". They don't have to go off-chain or touch their BTC or whatever, just click, click, click and boom, you have lots of HIVE.
On the flip side, if HIVE goes up to close to $1.00, it would be good to drop the savings ARP to 10% or 15% to provide incentive to divest from savings and sell their HBD for HIVE. It's all about providing reasons to BUY HIVE, either cheaply (FUD) or while it's on the rise (FOMO).
I am of course assuming HBD will always be $1.00. The sad reality is that under the right conditions it can overvalue or devalue, breaking it's peg with USD. Just my thoughts.
What you say is not wrong. The problem I see is that things could evolve quite fast if hive drops more in price. The lower the hive price, the higher the dept level and the closer we get to the haircut, where HBD automatically depegs. Suddenly you get 20% on your investment that might be worth only 80% of the capital. High HBD apr favorises a decrease of Hive prices which gets us closer to the haircut which in turn risks the peg. In my opinion the present situation isn't sustainable even if we don't see the effects yet.