Thats like saying a couple who has a 1 in a 1000 chance of producing a down syndrome baby shouldn't have kids.
Just because something might happen doesn't mean you shouldn't try for all the healthy offspring that will be much more likely to result from breeding a spider. I have a spider male in my collection. I plan on getting a female in the near future. My male has a slight wobble but he eats like a machine and is otherwise, normal. I will breed him despite his wobble. Now, if I get hatchling after hatchling after hatchling who are all trainwrecks, then I would no longer breed him.