I see Broner do it a lot and Floyd often on the Heavybag.
They simply slap instead of actually punching.
Why is that? Why would you wanna slap instead of punching for real especially on the hooks.
Speed... blind ya with speed to set up harder shots when opponent gets comfortable with the speed's power..
Plus it conserves energy..
Calzaghe had a hall of fame career, undefeated, 2 division lineal champ by slapping so it can be effective.