It would basically be a change to be either "invested" or "cashing out". If you wanted to cash out 20% of your funds, it would be removed from your voting power and dispersed over 3 months. The other 80% that was not being withdrawn would still be vested and count towards your voting + curation rewards.
Basically users would need to decide if their money is in or out.
But what if I want to cash out 20% in three weeks? A full powerdown under the proposal would accomplish that, yet I'd be penalized 100% during that time. IMO, this becomes very over-complicated and cumbersome. There seems no real value to it. Just let people vote on what is in their account, just like you would with votes on stocks. You either have them or you don't. If you sell them, it's done.