When your economics are muddled, you risk doing more harm than good. HBD's main function is STABILITY (of the peg to USD 1:1), not YIELD!
HBD is intended as a tool to make the Hive blockchain attractive to trade and to real world exchanges of goods and services. The yield is a tool to the end of STABILITY. The fact that a high yield has "broken the peg" on the upside means the yield should be REDUCED, not increased !
The objective of the witnesses should be to bring HBD back to 1 USD.
Therefore, yield should be managed like central banks manage their funds rate, and this means decreasing the yield resolutely, first to 5% I would say.
Meanwhile Hive should attract users in its own right through the apps that make it the best blockchain out there. Blogging, playing, etc
No need to repeat myself. You said it all.