I deleted mine with my real name, and created one with a fake name, since sometimes I have no other way to participate in stuff/with certain people socially.
It's still not enough. First-hand I've seen stuff like, they will make friend suggestions based on people accessing facebook from your IP Address. Crazy scenarios like:
Person A searches for Person B, maybe views their profile (doesn't even have to friend them). Person B has sometimes accessed FB from your IP address, and you get a friend recommendation for Person A.
My fake persona was born in Botswana, went to college in Russia, and lives in a town now that matches my first name. I get no recommendations for people in any of those regions/schools, I get friend recommendations of everyone my old account used to be friends with, and their connections.