Great comment! Yes I totally agree that in actual practice, for the largest accounts that always have a high expected payout on posting, we will definitely still see votes coming in before 15 minutes because of the curation hunters. Really it is similar to what we see now on auto-votes set up on large accounts - you don't see very many set to 30 minutes even though at first blush that might seem the optimal time - actual optimal time is going to be determined by behavior of other voters, and constrained by the diminishing returns the earlier you vote - for haejin/ranchorelaxos of the world I expect we will see incoming votes even earlier than the 12 minute vote.

I think your last suggestion is great, and on a related note I have actually been planning on commenting on the GITHUB proposal that an adjustment will need to be made to the automatic self-vote that an author can enable by clicking the box when posting - if that stays at 0 minutes it is obviously to the detriment of the author. Possibly that should be a slider (self vote at 0-15 minutes) with a note explaining possible diminishing returns on vote closer to 0.