User blog comment:Marijuanna/Visard before Turn back arc/@comment-8464927-20130827062524/@comment-1387259-20130827111015

I see what he's getting at with the line of thinking that it may have happened before, though. Plenty of laws are made because someone did something that could be considered "wrong" or "immoral" before it was illegal. While it may not be true for all laws (real or in the Bleach universe), it seems like Central 46 wouldn't have made a law about Shinigami gaining Hollow powers unless they knew that it was possible to at least try. So yeah, I'm thinking the failed experiment part.