Family hack? The Stareater, is that my project? Well gee, guess I should explain the trick!
Well, it is not a hack per se, just bit of a clever solution. What you do is add two or more families, depends how complex your picking code gets.
With two families, let's name 'em A and B, you can pick from other family INDEPENDENTLY of the SOL of first family. You see, families have their own SOL, as do objects. That is three different selected object lists!
So, with more than one family, when you are working with already selected members of family A, you can select another bunch from family B without messing the selected members of A up.
If it is too confusing, let me illustrate it:
You have balls. Normal, ordinary round balls, not the furry kind. Add two families to these balls, name them Red and Blue. Even if balls actually are pink, but who cares.
So, you have a condition that, say, filters balls by their relative position. Balls on the left side of the table, for example. You make a condition, using the family Red:
+Red.X < LayoutWidth/2 (Assuming the table is the size of a layout)
Now, we want to also pick balls that are on lower half of the table. But wait, we can't do that, we've already selected balls and if we refine search any more, we won't be able to grab balls on lower right! Oh wait, we've got one more family to abuse. Phew.
+Blue.Y < LayoutHeight/2
Now we have two selected groups of balls, first group of balls that are on left side of the table and second group of balls that are on lower half of the table! Two selections, independent of each other! You can make operations with them, like count them, see how many balls are in either group, which side of the table is more populated etc.
Within the same event. That, friends, is the beauty of multiple families; they grant you access to extra SOLs (Selected Object List or something, it remembers objects that passed the condition). You can combine this into elaborate picking procedures! Oh, and don't forget: objects have their own SOL as well, so that is three ways to abuse! Whee!
And that's it from me.