The problem with being forced to vote at a later time is that chunks of curation rewards are being forfeited. If it all would be randomized, I'd be okay with it, but if it's simply about people not wanting to see burn posts on trending; then this should have a direct UI solution.
While I was and still am a proponent of the SPS, much of it could have also been realized with the current voting mechanism we have today, just by having the right UI for it. So I think it's crucial that we do the right thing for people who want to burn rewards.
RE: Steem experiment: Burn post #563