The entire lesson took no more than ten minutes. Hermione was almost disappointed that the spell was so simple. Once she had the incantation and the wand movements locked away in her brain and she'd been able to perform it successfully a few times, she understood why Draco had been so afraid of the other Death Eaters learning the spell. Any one of them could've cast it. Even those who weren't especially blessed with brains would be just as good a tracker as he was if given the proper tools. He really would've been disposed of if the secret of his spell got out.