Hi Jesse:
I'm going to assume you mean eastern black walnut (Juglans nigra) since this question was posted to the "All About Black Walnut" category.
I'm aware of the bark feature you speak of; however, I absolutely would not use that external feature as a guide to select which black walnut trees trees to mark for harvest. I don't know of any research or anecdotal evidence to back-up that claim.
Thanks for your question!