Good article - thank you :)
Personally, I'd prefer to see regular small adjustments to the HBD interest rate if they are needed, rather than big swings either way which might suggest knee-jerk reactions. It's purely a confidence thing.
The one thing I would like to see is far more cost control over DHF funds issued to proposals (since that is where the largest HBD movements happen), in the form of more detail on how the funds will be used, objective metrics which would demonstrate a project is a success, and hard data to confirm whether those metrics are being achieved.