The Fold Map is possibly one of the more obscure references I've made. Luckily, since it's a relatively simple conjunction of two mundane words, and in any case doesn't work in the same way as its source, I don't think anyone would be in a position to object to its use here. Points to anyone who knows where I got the phrase from!

EDITED TO ADD: Also, the phrase "First trick he learned" is an intentional nod to Watchmen.