How large an amount is meant by "relatively small"? Do you know? Does he specify? See, that word "relatively" is important, here. Is it "relative to how much the layperson might think"? Is it "relative to the atomic bomb"? Unless you know to what the amount is relative, you have no information that's actually useful. Heck, I'll say a relatively small amount would be needed--and that's relative to the size of the building.
"Now everyone was giving her that kind of look UFOlogists get when they suddenly say, 'Hey, if you shade your eyes you can see it is just a flock of geese after all.'"
"You can't erase icing."
"I can't believe it doesn't work! I found it on the internet, man!"