Good point. I forgot to address changing user preferences. To adapt to changing user preferences, the set of content instances considered by my proposed algorithm could be a sliding window excluding old content, or probably better would be to weight the older instances less in the computation of the mean for Dₛₜ.

So far, I can’t think of any computation of rankings by tags without the clustering by voter like-mindedness, which is any different from the current algorithm; and thus won't stop the optimum voting strategy from being for everyone to vote in a groupthink for the most highly voted content.

Thanks to everyone who appreciated the proposal. We need to spend more time thinking about any vulnerabilities it might introduce. I wanted to get the proposal published as soon as possible. I will be pondering it.