I also think if you're honest with yourself and really critique your own horses, you will automatically weed out those horses that have poor conformation, thus (probably) eliminating horses that may carry or minimally express the dwarf gene.
I think my smallest horse looks a little 'off' and I'm wondering if she is possibly dwarfish... I'm not going to breed her until I get someone to take a look at her... Her body is stocky, but I'm not fond of stocky horses to begin with, so don't know if my own prejudice is showing through... When I look at a horse, I visually create a box (square, not rectangular) around the horse. Hip to withers, withers down to the ground just behind the front hooves, then front hooves to back hooves and then back up to the hip... I want a horse that is 'square' (in addition to other conformation qualities).
Nikki (LTD's Fashionique - you can see her complete pedigree on All Breed Pedigree) just doesn't look square to me... Her dam is a bit stocky now, but was AMHR 2004 Top Ten Amateur Halter Sr. Mare, Under (5th) and a daughter of LTD's Magic Man and her sire is AMHR 2004 Reserve National Champion Amateur Halter, Jr. Stallions, Under and is an Magic Man grandson. She also goes back to Samples several times... So, she's got excellent breeding out the wazoo, but according to John Eberth, nearly all of our bloodlines have dwarfism somewhere in their backgrounds...
Oh, you can see a pic of her on LTDs website... In that pic, she looks square, so maybe she is just pudgy now. lol!
Kari