This is non sense. There is no such thing as a "line" without the wobble. It cannot be selectively bred out.
This is because the mechanism during embryonic development that inhibits the distribution of pigment (causing the spider pattern) is disrupted or blocked through the nervous system in the spinal cord. I dont really have the techincal expertise to explain it well, but ive found some very informative scientific resources online on the subject.
The point being, a mutated gene that reduces pattern by blocking neurological processes during development will always have other neurological side effects. You cant separate the two out, because they are both caused by the same mutated gene having the same effect during development.
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