That would only apply if you're the only person voting for yourself which is unlikely - otherwise the curation part is shared with everyone else - so everyone who votes gets a share (proportionate to their vote value) of the curation part.
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But the same thing applies whether it is 75/25 or 50/50, so the question is, why would this difference of probably a small percentage stop someone from self voting?
Self voting is still the most profitable in 50-50, but I think the idea is (I got this from @clayboyn's post which i linked to above) is that with the rebalancing more people will curate other people's posts in the hope that those posts will get trended to the highest earning spot and thus curation rewards will be greater.
Add to that the bonus of having a decent content discovery system through curation and it should increase eyes on the platform and thus increase the steem price.
It is just a tweak to incentivising people away from SV, it may not be enough.