This is different from what i have heard from others.
It is not like before, just changed from 30 to 15 minutes.
Before, it was earlier, more reward went to the author.
Now, it is that portion goes to the rewards pool.
And i haven't found anyone that is certain whether it is a sliding scale from 0-15 minutes.
Seems like a really easy thing to test. Unfortunately, I never completely my curation tracker because the dumb dumbs at Steemit INC don't include block information inside the Discussion object.
The curation curve doesn't get sent to the author, it goes back into the reward pool it seems. It's not like before completely indeed.