There's nothing wrong with scoring slowly if the context of the match demands it. A rather more adventurous approach would have been perfectly appropriate on Saturday afternoon. Instead, Cook decided - as ever - to grind it out.
Boycs wasn't always the prettiest, but that wasn't his job. He had superb defensive technique, which meant he was a bástard to dislodge. Cook doesn't have superb defensive technique - he's just dull.