Yes, it's indicative of the model and age. Some models used nail nicks, some used long pulls. And some long-pull models were match strikes at one time. There were different match strike patterns too. Unfortunately there's no exact date as to when a knife model switched from one to another, but it can narrow down the knife's era. Production changes (nail nicks, tang stamps, box styles) seem to be determined by when the factory ran out of the old style and started using the new. 
