What strategies can be employed to effectively manage pace in a group setting, particularly when riding with varying levels of experience and fitness, and how can one balance the need to conserve energy with the desire to maintain a competitive edge? Are there specific drills or training exercises that can help improve pace management, and what role does communication play in ensuring a harmonious and efficient group ride? Additionally, how can riders adapt their pace management strategies to accommodate different terrain and weather conditions, and what are some common mistakes to avoid when trying to manage pace in a group setting?