Part of the new issued coins are allocated to SP holders. This means that the less Steem is powered up the more coins are being allocated to existing SP holders. So the new changes ( more liquid steem) basically creates a new incentive to stay powered up because there would be less steem powered up. Please let me know if I am missing something but that's how I understand it.
Yes this is correct. When the percentage of SP is less than 90%, then there is an apprecation of share aggregating to the SP holders. This increases as the SP share decreases. I had covered this math in one of my blogs or comment posts on Steem. It is linked upthread some where in this thread.
The chart is here and the detailed math discussion is in the comments:
https://steemit.com/steem/@anonymint/who-pays-for-the-blogging-and-curation-rewards-part-2