On The Gist, Mike asks Maria Konnikova of the New Yorker to explain the link between seasonal affective disorder and winter blues. Is it a real condition, or an overly convenient acronym? For the Spiel, why arguing aboutinstant replays is a beloved American pastime. Today’s sponsors: Monster. Find employees who work as hard as you at Monster.com/hiring. Monster. Find Better.  Betterment, the largest automated investing service—managing billions of dollars for people just like you. Get up to six months of investing free when you go to Betterment.com/gist.  Join Slate Plus! Members get bonus segments, exclusive member-only podcasts, and more. Sign upfor a free trial today at slate.com/gistplus. Learn more about your ad choices. Visit megaphone.fm/adchoices