Anecdotal - a friend of mine still farms full time. He row crops in the midwest US. One of his fields butts up against the local small town. Last year, on the north side of the field, the rows are arrow straight. The south side were squirrely and curved all over compared to them.

When I asked what the hell happened, he said the auto-steer went out, and by the time he figured out how to even run the planter while it was planting, he was done.

He laughed and said that the biggest problem wasn't the loss in yield, it was that he dropped his psp and broke it.