Running

Unless there's a headwind the only advantage in sitting behind is stressing out your opponent, there's no drafting advantage if no headwind, you aren't going fast enough when running- However, no one likes someone breathing down their neck and not being able to see them, its a psychological see your enemy at all times thing.

but isn't his point that if you're the fastest and you're just going flat out then a surge shouldn't be able to catch you

This.

during the mens marathon in rio gold winner kipchoge chastised the silver runner for trying to slipstream him and basically told him to run to his side if he wanted to stay with him. when he didn't kipchoge just opened the taps and burned him off and the silver guys race was done. if he'd let him sit behind him for a few more km chances are the silver runner might have had enough left to out sprint him for the final stretch.

If this is the case and drafting makes a difference then it changes the whole game and the tactics make sense, but aero doesn't apply at my speed and if it applies to the pros then why the flappy clothing?

EDIT: new page. @Spares if it's all about psychology then wouldn't the front runner get a "hell yeah! I'm winning!" boost? I certainly do when I find myself unexpectedly well placed in the local xc league.

Also, these guys are professional athletes... They presumably have exceptionally high drive and self belief or they wouldn't have made it to the Olympics and many teams will have psychologists dedicated to helping the athletes overcome the stresses of racing.