I was just thinking about this:

It would be interesting to see how whales that have spread their stake around to alt accounts for specific reasons or just "for fun" might "abuse" this system by confusingly moving their funds around.

Alternatively, to circumvent such abusive behavior, we could decide to first only have Steem/SP and SBD/SP pairs available at the internal market, and no direct OTC option available between two accounts directly. As a direct consequence, "abusers" would not have a direct way to transfer their stake from alt account A to B.