Final answer:
The statement that consistently flying in trail allows the enemy to place raking fire across the formation, and observation of the team is reduced is true.
Step-by-step explanation:
The statement is true. Flying in trail formation exposes an aircraft group to several disadvantages in a combat situation. This type of formation makes it easier for the enemy to predict the flight path and potentially apply raking fire across the formation. Raking fire is effective because it can simultaneously damage multiple aircraft. Conversely, flying in trail can hinder the observation of the entire team, as each aircraft's view is limited to that of the aircraft directly in front, reducing situational awareness and the ability to react to threats from other directions. As referenced in the information given, a successful general must understand the importance of proper troop formation and placement. This aligns with points mentioned, such as the value of using the natural formation of the country as an ally and the necessity of calculating difficulties and dangers, which includes understanding and using effective formations during combat.