Tautologies At Work

From the 'Everyday math' Dept.:

Ever wonder how it is that every auto insurance company that contacts you claims they can save you $500/yr.? Presh Talwalkar wondered, and explains in his latest "Mind Your Decisions" post:

http://tinyurl.com/o9ls4ms

(...basically an insurer CAN save you $500 IF, by switching to them, you will save $500 ;-) otherwise known as 'selection bias' in advertising*)

* "advertising" -- otherwise known as propaganda