User blog comment:Emptylord/Champion reworks/Rammus the Guardian of the Sands/@comment-24420226-20160520000554/@comment-3974211-20160520005735

I intended for the shield to be self-modifying, in a sense, but I want it to be ridiculously hard to break.

And granted on the anti-pattern. The intent was more that it explodes when the effect ends, not just if broken, but that distinction doesn't change the visceral response players will have. It's an obnoxiously potent shield - maybe that's enough.