Effect of "Flight of Foot" and upgrades?

[ZerkerDwarf]

The description of "Flight of Foot" level 13 and its upgrades says"Increases the agility of the swashbuckler and increases the effectiveness of all combat arts used by the swashbuckler."How are the combat arts' effects increased? More damage? Better chance to hit? Both?

[adamflanagan]

the flight of foot line is an agility and strength buff. Strength increases auto attack and combat art damage.