Having a 3rd person mode would give people the ability to look around corners without peeking, which would destroy the gameplay, as there is no risk to scouting.
I agree but it all depends on how the camera view is implemented. Also if they choose to make the ability a pick-up, then 3rd person would be like using any other weapon or pick-up like a flying drone for example...
Allowing 3rd person to be a choice anyone can use at anytime, makes using it a tactical decision. First person has its advantage in some situations and third person can have its own advantages in others. Knowing when to use the proper view at the right time then becomes an additional skill.
And for those that get motion sickness in first person mode, this would be a welcome addition without having to have separate servers for first person and third person players.
