Heavier than stock pistons you will need to add Mallory to the crank.
Lighter than stock pistons you will need to remove weight from the crank.
Does this make sense?
Yes. I get the concept of the balancing process. As far as I can tell There is not a machine shop around me that can do the balance work for anywhere close to $250. So Its a big expense that I am trying to make sure its a must not a should kind of thing. Most guys local seem to think its important once you start to spin a motor over 6000rpm. Other than that not necessary.