In the May 11 issue of The New Yorker, statistics nerd Malcolm Gladwell notes that underdogs — specifically in war — actually win their battles against much bigger opponents about a third of the time.

In 1970, a pair of Canadian promoters decided they'd throw a series of rock festivals across the Great White North, signed up the likes of the Grateful Dead, Janis Joplin, The Band and Buddy Guy to ...