Here's a thought: there has to be an auto-wipe mechanism if the data corrupts (let's hope, anyway). probably not too hard to trigger that.
Traditionally in cases like these, there's actually two save slots. When it saves the game, it goes into the 'other' slot, and only upon successfully saving it moves itself into the main slot.
And I thought that Nintendo did require a way to reset all game data (even if it was some obscure button combo) for the GBA/DS/3DS? Apparently not.