This change does not really open up a new form of abuse. What you described is possible today. If I am a large stakeholder today and I want to incentivize a large number of votes prior to my self-vote, I can just wait 30 minutes and vote then.

There will always be an economic incentive for curators to lead the votes of large stakeholders whose votes they can predict. In my view, if we are to address this problem we need to look more into ways to lower the rewards on content that is receiving a higher payout than it is worth (i.e. downvoting).