There is a separate conversation to be had about downvoting in general. Even without this experiment, there are tons of users that are downvoting to counter other people's votes. (Dan is doing it, Bernie is doing it, Smooth is doing it..) 

There is still a lot of disagreement over it, but the general consensus is that anyone is allowed to upvote/downvote however they chose. It is their SP, and if they want to use it to cancel someone else's vote - that is entirely within their right as a SP holder.

> This experiment will not even provide us with an untainted dataset

I do not know what the goals of the experiment are. I would imagine that after all the dust settles from the initial drama over people getting downvoted, the dolphins and minnows may actually enjoy the platform quite a bit more for the duration of the experiment. Personally, I like how my upvote can actually make a few cents of difference now.

I know it's been said before, but this would be a lot different conversation if this was something permanent. Obviously this would not be fair to the main stakeholders of the platform, and I suspect most of them would power down and either cash out, or power up a bunch of little accounts to get around it.

Since it is a temporary experiment, I see the potential harm as fairly minimal.