Quote from Barney in Shelter Island
Barney: [off Lily's look] What? Lily: No "Don't get married, Ted"? No "You're making a big mistake, Ted"? Barney Stinson, are you no longer committed to the war on marriage? Barney: No, I just know a hopeless cause when I see it. It's the same reason I don't recycle. Plus, Ted getting married is in my best interest. [v.o.] You see, lately I've been working on a problem of the utmost importance. I confess I was stumped. Until one night I decided to tackle it once and for all. [Barney at work writes an equation on a board titled "How can I have sex with Robin again?" Various words light up: VULNERABLE, NOSTALGIC, BOOZE] Barney: [v.o.] Then, at last... I cracked the code. [GET HER DRUNK AT TED'S WEDDING]