I do know that the intent of the window is because it is too resource intensive to keep reward calculations open for all posts indefinitely.
The method you propose sounds interesting, as it creates a workaround that would only trigger when a post generates renewed or continual interest. Honestly, the vast majority of social media style posts don’t see any prolonged activity. No one goes back to a two year old image of someone’s dinner and likes it!
I’ve previously advocated for a different “hack” with the same intent. An interface or interfaces should develop a “resteem with comment” option. I remember seeing this even listed as something that could be implemented with new Hivemind tools. But, the step further I’d like to see, is for that “share” style to automatically reference the author of the shared post and set them as a fairly significant rewards beneficiary.
So for instance, I find an awesome year old tutorial you did, and resteem it on my blog with a comment for my followers to check it out. I get 30-40% of any rewards my share generates, and 60-70% goes to you. This creates an “evergreen” revenue stream for posts, encourages resteems and sharing, and a whole new breed of curation rewards emerges, that greatly benefits casual users with low SP holdings that don’t benefit from curation rewards now due to the low impact of their votes.
True enough about typically social media post not generating continued interest, which is why I think this could work without bogging down the system. It would benefit the few cases where someone shares content that does create renewed interest like, a tutorial, or a music video, or artwork, etc. It would shift the incentives here to quality over quantity.
Also love the resteem idea, I think it would be cool if the poster could set the amount with like a minimum of 15% or something. But imagine you're promoting something, you might set it to 100% if your primary goal is to spread the word about something.
I like that aspect of it being a customizable field set by the author. You’re absolutely right it could be a strategy to get more exposure and promotion.
After thinking more about my reply, I thought of a troublesome exploit though, someone would post something on account A, have 100 alt accounts that all resteem the post and have account A set the beneficiary amount to where the resteemers get 100% of the payout.