I agree with nearly everything I have read you say @dana-edwards. I honestly dont see why steem would spike from someone buying and powering up on this news. Me thinks it be a bit of a rare coincidence...and that guy/gal will likely be quite angry then they see this change to steempower.
Let people build on steem and stop worrying about the other stuff. Steem and steempower work! Or see my other post if you must do something like this, only include the scale where everyone can choose what level of steempower they want to have.
It's a tax on Steem Power holders because the interest is being reduced. I understand the need to reward bloggers and curators but it's really hard not to perceive of it as a tax and a tax on the wrong people in my opinion.
In any case will it raise demand? I have my doubts that any quick fix or economic band aid will raise demand. I think raising demand takes months of iterative improvement in UX/UI and features.