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Maybe the purpose of this proposal is discouraging "not surveying"?

I think the actual purpose is to encourage people to continue to participate, considering the original proposal was enacted due to the delays associated with land. More functionality is being added, so people should no longer be rewarded for being passive-- they need to take the next step to continue to earn rewards.

Maybe land token flipping?

More likely more surveyed land flipping in the short term, as people who don't want to hold common and rare plots sell them off.