Agreed something is in the water that has this place all stirred up.

Your point on pelvic size well taken, it would relate back to dystocia in general as being genetic.

Truth be it we always blamed a backward calf on the Bull.  He put the seed in wrong. Think that's how the old man said it. (Its a joke guys)

  Would call backwards calf a numbers game.  That does have some environmental causes, calf size, exercise, twinning, but never heard of Genetic.   Per dystocia nothing showing is the hardest call in the book.  Recognize it and move forward accordingly.  Hope for a good outcome.