Outside of exploiting (and multiboxing imo) all is fair in open world pvp. Camping rez's, quest hubs and entrances is part of the game and adds the "danger" element to the moors - hunt or be hunted. You want complete safety while farming/gearing I would suggest playing freepside for the training wheels
With organized 1v1s you can intro "fair play" into the equation with consumable/skill restrictions, but frankly I wouldn't expect it. And I would definitely not expect it in a random encounter out there.
PS - server xfer submitted