I don’t know what’s more rampant on the web: writing advice or weight loss tips. They have common features. An authoritarian tone — Don’t do this! Do that ! — and a shine of expertise. I confess, I’m better at dismissing fad diets and miracle exercise routines than articles that pretend to help me write a killer first sentence. It’s no surprise that I’m always disappointed. If there was a foolproof trick, all scribblers would use it.