Well, I don't deny nor confirm my involvement with the creeper face mafia.
But I do remember taking a leap of faith and breaking one piece of cobblestone next to an Iron Door, but I immediately replaced it correctly, as far as I can remember. It was the door blocking the corridor you get into from a breech in the wall covered by a wooden door facing the lake and the tower in the middle of it. If I remember, that wasn't even the correct entrance to that labyrinthical compound. I don't know how I got in there, and I sure don't know how I got out either!
This is the only thing I'm not proud of. Needless to say, if there were redstone, water, lava, sand or gravel it would've been a very ugly mess. This is the only block from somebody's building that I ever broke. Gladly, it was harmless, but it could've been very much different, and I fully regret doing it.
In any case, today I am going away for a week, so your buildings, cakes and cactuses should be safe for the moment.
*You hear the sound of applause and whistling*