Sort:  

I agree. Right now, someone is basically using Steemit's own stake to attack the blockchain (I checked 6 more accounts, and they all had 15SP delegations, too). This should be prevented. As I thought about it some more, even that is not as easy as it sounds, though. They'd still have to either (i) automate the delegation removal, which would - in turn - be abused; or (ii) manually verify every report, which could become overwhelming.

The best option might be for the community to actually make use of the downvote mechanism, and then steemit could automatically remove the delegation for any user whose reputation drops below some level. (I might even remember reading that they already have this automation in place, but I'm not sure.)

yep, that is perfect. Once Rep hits... X remove it. @steemit

Maybe they could even encourage people to participate with a "bounty", of sorts. If your downvote triggers a delegation removal, then you'll get an equivalent delegation for a period of N days.