This makes us obliged to go through the entire ancestor history of a comment every time we wish to make a reply if we wish to avoid being arbitrarily punished.
Since the system, as it works now, asks whether we really wish to spend karma, we wouldn't need to go through. Nevertheless I agree with the latter part of your comment.
Has anyone yet mentioned or reported that for the last couple days, the "karma for last 30 days" is showing zero for everyone? And that we no longer can see the top contributors for the last 30 days either?
Do we have an explanation or estimation for a bugfix on this?