The speed bonus for arrows ( not sure if all projectiles ) got increased in one recent patch, which means, or should mean that moving into a projectile deals considerably more damge, while moving away from the projectile gives considerably less.
Upon damage testing on EU3 after the patch however ( when the "B" show damage was still there ), it turned out that a shot with speed bonus was actually doing less damage than a stationary hit. Couldnt contact San about this yet.