The Secret Life of Water Mitty, which debuted on Saturday at the New York Film Festival, is for saps. I'm using the word "sap" in the most positive way possible. (And, I'll admit, I am a bit of a sap because I enjoyed The Secret Life of Walter Mitty.) Mitty's greatest asset - its earnestness - may be, at the same time, its greatest detriment, because this is the year 2013 and "earnestness" is not always looked upon as a desirable attribute these days. And, boy isWalter Mitty earnest.