I would say you are effectively doing the same thing even if your trying to hit something smaller so either you...
1) Still have to take down the same 4 stud damage (1 stud damage to do what is in essence the same thing is cheap and lame and not very sportsmanlike).
2) Trade off the 1 stud damage for a hefty mod to hit the smaller moving target.
Either way you should always have to pay for your cunning success, there are no free lunches and I hear the cake is a lie. But this is only my way of thinking, others may have better advice.